diff --git a/lib/markets/altmarkets.js b/lib/markets/altmarkets.js
index f1028d4..2862b16 100644
--- a/lib/markets/altmarkets.js
+++ b/lib/markets/altmarkets.js
@@ -33,14 +33,14 @@ function get_summary(coin, exchange, api_error_msg, cb) {
             else {
               try {
                 const summary = {
-                  'high': parseFloat(tic_body.ticker.high),
-                  'low': parseFloat(tic_body.ticker.low),
-                  'volume': parseFloat(tic_body.ticker.amount),
-                  'volume_btc': parseFloat(tic_body.ticker.volume),
-                  'bid': parseFloat(order_body != null && order_body.bids != null && order_body.bids.length > 0 ? order_body.bids[0].price : 0),
-                  'ask': parseFloat(order_body != null && order_body.asks != null && order_body.asks.length > 0 ? order_body.asks[0].price : 0),
-                  'last': parseFloat(tic_body.ticker.last),
-                  'change': parseFloat(tic_body.ticker.price_change_percent.toString().replace('%', ''))
+                  'high': parseFloat(tic_body.ticker.high) || 0,
+                  'low': parseFloat(tic_body.ticker.low) || 0,
+                  'volume': parseFloat(tic_body.ticker.amount) || 0,
+                  'volume_btc': parseFloat(tic_body.ticker.volume) || 0,
+                  'bid': parseFloat(order_body != null && order_body.bids != null && order_body.bids.length > 0 ? order_body.bids[0].price : 0) || 0,
+                  'ask': parseFloat(order_body != null && order_body.asks != null && order_body.asks.length > 0 ? order_body.asks[0].price : 0) || 0,
+                  'last': parseFloat(tic_body.ticker.last) || 0,
+                  'change': parseFloat(tic_body.ticker.price_change_percent.toString().replace('%', '')) || 0
                 };
 
                 return cb(null, summary);
@@ -74,8 +74,8 @@ function get_trades(coin, exchange, api_error_msg, cb) {
           for (let t = 0; t < body.length; t++) {
             trades.push({
               ordertype: body[t].taker_type.toString().toUpperCase(),
-              price: parseFloat(body[t].price),
-              quantity: parseFloat(body[t].amount),
+              price: parseFloat(body[t].price) || 0,
+              quantity: parseFloat(body[t].amount) || 0,
               timestamp: parseInt(body[t].created_at)
             });
           }
@@ -107,15 +107,15 @@ function get_orders(coin, exchange, api_error_msg, cb) {
 
         for (let b = 0; b < body.bids.length; b++) {
           buys.push({
-            price: parseFloat(body.bids[b][0]),
-            quantity: parseFloat(body.bids[b][1])
+            price: parseFloat(body.bids[b][0]) || 0,
+            quantity: parseFloat(body.bids[b][1]) || 0
           });
         }
 
         for (let s = 0; s < body.asks.length; s++) {
           sells.push({
-            price: parseFloat(body.asks[s][0]),
-            quantity: parseFloat(body.asks[s][1])
+            price: parseFloat(body.asks[s][0]) || 0,
+            quantity: parseFloat(body.asks[s][1]) || 0
           });
         }
 
@@ -148,10 +148,10 @@ function get_chartdata(coin, exchange, api_error_msg, cb) {
           for (let c = 0; c < body.length; c++)
             chartdata.push([
               parseInt(body[c][0]) * 1000,
-              parseFloat(body[c][1]),
-              parseFloat(body[c][2]),
-              parseFloat(body[c][3]),
-              parseFloat(body[c][4])
+              parseFloat(body[c][1]) || 0,
+              parseFloat(body[c][2]) || 0,
+              parseFloat(body[c][3]) || 0,
+              parseFloat(body[c][4]) || 0
             ]);
 
           return cb(null, chartdata);
diff --git a/lib/markets/bittrex.js b/lib/markets/bittrex.js
index 2420e37..01921fd 100644
--- a/lib/markets/bittrex.js
+++ b/lib/markets/bittrex.js
@@ -33,13 +33,13 @@ function get_summary(coin, exchange, api_error_msg, cb) {
             else {
               try {
                 const summary = {
-                  'high': parseFloat(sum_body.high),
-                  'low': parseFloat(sum_body.low),
-                  'volume': parseFloat(sum_body.volume),
-                  'bid': parseFloat(tic_body.bidRate),
-                  'ask': parseFloat(tic_body.askRate),
-                  'last': parseFloat(tic_body.lastTradeRate),
-                  'change': parseFloat(sum_body.percentChange)
+                  'high': parseFloat(sum_body.high) || 0,
+                  'low': parseFloat(sum_body.low) || 0,
+                  'volume': parseFloat(sum_body.volume) || 0,
+                  'bid': parseFloat(tic_body.bidRate) || 0,
+                  'ask': parseFloat(tic_body.askRate) || 0,
+                  'last': parseFloat(tic_body.lastTradeRate) || 0,
+                  'change': parseFloat(sum_body.percentChange) || 0
                 };
 
                 return cb(null, summary);
@@ -73,8 +73,8 @@ function get_trades(coin, exchange, api_error_msg, cb) {
           for (let t = 0; t < body.length; t++) {
             trades.push({
               ordertype: body[t].takerSide,
-              price: parseFloat(body[t].rate),
-              quantity: parseFloat(body[t].quantity),
+              price: parseFloat(body[t].rate) || 0,
+              quantity: parseFloat(body[t].quantity) || 0,
               timestamp: parseInt(new Date(body[t].executedAt).getTime() / 1000)
             });
           }
@@ -106,15 +106,15 @@ function get_orders(coin, exchange, api_error_msg, cb) {
 
         for (let b = 0; b < body.bid.length; b++) {
           buys.push({
-            price: parseFloat(body.bid[b].rate),
-            quantity: parseFloat(body.bid[b].quantity)
+            price: parseFloat(body.bid[b].rate) || 0,
+            quantity: parseFloat(body.bid[b].quantity) || 0
           });
         }
 
         for (let s = 0; s < body.ask.length; s++) {
           sells.push({
-            price: parseFloat(body.ask[s].rate),
-            quantity: parseFloat(body.ask[s].quantity)
+            price: parseFloat(body.ask[s].rate) || 0,
+            quantity: parseFloat(body.ask[s].quantity) || 0
           });
         }
 
@@ -149,10 +149,10 @@ function get_chartdata(coin, exchange, api_error_msg, cb) {
             if (new Date(body[c].startsAt).getTime() / 1000 > start && (c % 3) == 0) 
               chartdata.push([
                 parseInt(new Date(body[c].startsAt).getTime()),
-                parseFloat(body[c].open),
-                parseFloat(body[c].high),
-                parseFloat(body[c].low),
-                parseFloat(body[c].close)
+                parseFloat(body[c].open) || 0,
+                parseFloat(body[c].high) || 0,
+                parseFloat(body[c].low) || 0,
+                parseFloat(body[c].close) || 0
               ]);
           }
 
diff --git a/lib/markets/dextrade.js b/lib/markets/dextrade.js
index b221f15..0b625c8 100644
--- a/lib/markets/dextrade.js
+++ b/lib/markets/dextrade.js
@@ -22,12 +22,12 @@ function get_summary(coin, exchange, api_error_msg, bid, ask, cb) {
       else {
         try {
           const summary = {
-            'high': parseFloat(body.data.high),
-            'low': parseFloat(body.data.low),
-            'volume': parseFloat(body.data.volume_24H),
-            'bid': parseFloat(bid),
-            'ask': parseFloat(ask),
-            'last': parseFloat(body.data.last)
+            'high': parseFloat(body.data.high) || 0,
+            'low': parseFloat(body.data.low) || 0,
+            'volume': parseFloat(body.data.volume_24H) || 0,
+            'bid': parseFloat(bid) || 0,
+            'ask': parseFloat(ask) || 0,
+            'last': parseFloat(body.data.last) || 0
           };
 
           return cb(null, summary);
@@ -58,8 +58,8 @@ function get_trades(coin, exchange, api_error_msg, cb) {
           for (let t = 0; t < body.data.length; t++) {
             trades.push({
               ordertype: body.data[t].type,
-              price: parseFloat(body.data[t].rate),
-              quantity: parseFloat(body.data[t].volume),
+              price: parseFloat(body.data[t].rate) || 0,
+              quantity: parseFloat(body.data[t].volume) || 0,
               timestamp: parseInt(body.data[t].timestamp)
             });
           }
@@ -91,15 +91,15 @@ function get_orders(coin, exchange, api_error_msg, cb) {
 
         for (let b = 0; b < body.data.buy.length; b++) {
           buys.push({
-            price: parseFloat(body.data.buy[b].rate),
-            quantity: parseFloat(body.data.buy[b].volume)
+            price: parseFloat(body.data.buy[b].rate) || 0,
+            quantity: parseFloat(body.data.buy[b].volume) || 0
           });
         }
 
         for (let s = 0; s < body.data.sell.length; s++) {
           sells.push({
-            price: parseFloat(body.data.sell[s].rate),
-            quantity: parseFloat(body.data.sell[s].volume)
+            price: parseFloat(body.data.sell[s].rate) || 0,
+            quantity: parseFloat(body.data.sell[s].volume) || 0
           });
         }
 
@@ -132,10 +132,10 @@ function get_chartdata(coin, exchange, api_error_msg, cb) {
             if ((body[c].time * 1000) > start)
               chartdata.push([
                 parseInt(body[c].time * 1000),
-                parseFloat(body[c].open),
-                parseFloat(body[c].high),
-                parseFloat(body[c].low),
-                parseFloat(body[c].close)
+                parseFloat(body[c].open) || 0,
+                parseFloat(body[c].high) || 0,
+                parseFloat(body[c].low) || 0,
+                parseFloat(body[c].close) || 0
               ]);
           }
 
diff --git a/lib/markets/freiexchange.js b/lib/markets/freiexchange.js
index ad21458..581b32f 100644
--- a/lib/markets/freiexchange.js
+++ b/lib/markets/freiexchange.js
@@ -7,7 +7,7 @@ const rateLimitLib = require('../ratelimit');
 const rateLimit = new rateLimitLib.RateLimit(1, 2000, false);
 
 function get_summary(coin, exchange, api_error_msg, cb) {
-  const req_url = base_url + '/ticker/' + coin;
+  const req_url = base_url + 'ticker/' + coin;
 
   // pause for 2 seconds before continuing
   rateLimit.schedule(function() {
@@ -22,14 +22,14 @@ function get_summary(coin, exchange, api_error_msg, cb) {
         try {
           const prefix = body[coin + '_' + exchange];
           const summary = {
-            'high': parseFloat(prefix[0].high),
-            'low': parseFloat(prefix[0].low),
-            'volume': parseFloat(prefix[0].volume24h),
-            'volume_btc': parseFloat(prefix[0].volume24h_btc),
-            'bid': parseFloat(prefix[0].highestBuy),
-            'ask': parseFloat(prefix[0].lowestSell),
-            'last': parseFloat(prefix[0].last),
-            'change': parseFloat(prefix[0].percent_change_24h)
+            'high': parseFloat(prefix[0].high) || 0,
+            'low': parseFloat(prefix[0].low) || 0,
+            'volume': parseFloat(prefix[0].volume24h) || 0,
+            'volume_btc': parseFloat(prefix[0][`volume24h_${exchange.toLowerCase()}`]) || 0,
+            'bid': parseFloat(prefix[0].highestBuy) || 0,
+            'ask': parseFloat(prefix[0].lowestSell) || 0,
+            'last': parseFloat(prefix[0].last) || 0,
+            'change': parseFloat(prefix[0].percent_change_24h) || 0
           };
 
           return cb(null, summary);
@@ -42,7 +42,7 @@ function get_summary(coin, exchange, api_error_msg, cb) {
 }
 
 function get_trades(coin, exchange, api_error_msg, cb) {
-  const req_url = base_url + '/trades/' + coin + (exchange == 'LTC' ? '/LTC' : '');
+  const req_url = base_url + 'trades/' + coin + (exchange == 'LTC' ? '/LTC' : '');
 
   // pause for 2 seconds before continuing
   rateLimit.schedule(function() {
@@ -60,8 +60,8 @@ function get_trades(coin, exchange, api_error_msg, cb) {
           for (let t = 0; t < body.length; t++) {
             trades.push({
               ordertype: body[t].type,
-              price: parseFloat(body[t].price),
-              quantity: parseFloat(body[t].total_coin),
+              price: parseFloat(body[t].price) || 0,
+              quantity: parseFloat(body[t].total_coin) || 0,
               timestamp: parseInt(new Date(body[t].time.toString().replace(' ', 'T') + 'Z').getTime() / 1000)
             });
           }
@@ -76,7 +76,7 @@ function get_trades(coin, exchange, api_error_msg, cb) {
 }
 
 function get_orders(coin, exchange, api_error_msg, cb) {
-  const req_url = base_url + '/orderbook/' + coin + (exchange == 'LTC' ? '/LTC' : '');
+  const req_url = base_url + 'orderbook/' + coin + (exchange == 'LTC' ? '/LTC' : '');
 
   // NOTE: no need to pause here because this is the first api call
   request({uri: req_url, json: true}, function (error, response, body) {
@@ -93,15 +93,15 @@ function get_orders(coin, exchange, api_error_msg, cb) {
 
         for (let b = 0; b < body.BUY.length; b++) {
           buys.push({
-            price: parseFloat(body.BUY[b].price),
-            quantity: parseFloat(body.BUY[b].amount)
+            price: parseFloat(body.BUY[b].price) || 0,
+            quantity: parseFloat(body.BUY[b].amount) || 0
           });
         }
 
         for (let s = 0; s < body.SELL.length; s++) {
           sells.push({
-            price: parseFloat(body.SELL[s].price),
-            quantity: parseFloat(body.SELL[s].amount)
+            price: parseFloat(body.SELL[s].price) || 0,
+            quantity: parseFloat(body.SELL[s].amount) || 0
           });
         }
 
diff --git a/lib/markets/poloniex.js b/lib/markets/poloniex.js
index fde8a1a..74e3605 100644
--- a/lib/markets/poloniex.js
+++ b/lib/markets/poloniex.js
@@ -21,13 +21,13 @@ function get_summary(coin, exchange, api_error_msg, cb) {
       else {
         try {
           const summary = {
-            'high': parseFloat(body.high),
-            'low': parseFloat(body.low),
-            'volume': parseFloat(body.quantity),
-            'volume_btc': parseFloat(body.amount),
-            'bid': parseFloat(body.bid),
-            'ask': parseFloat(body.ask),
-            'change': parseFloat(body.dailyChange) * 100
+            'high': parseFloat(body.high) || 0,
+            'low': parseFloat(body.low) || 0,
+            'volume': parseFloat(body.quantity) || 0,
+            'volume_btc': parseFloat(body.amount) || 0,
+            'bid': parseFloat(body.bid) || 0,
+            'ask': parseFloat(body.ask) || 0,
+            'change': parseFloat(body.dailyChange || 0) * 100
           };
 
           return cb(null, summary);
@@ -58,8 +58,8 @@ function get_trades(coin, exchange, api_error_msg, cb) {
           for (let t = 0; t < body.length; t++) {
             trades.push({
               ordertype: body[t].takerSide,
-              price: parseFloat(body[t].price),
-              quantity: parseFloat(body[t].quantity),
+              price: parseFloat(body[t].price) || 0,
+              quantity: parseFloat(body[t].quantity) || 0,
               timestamp: parseInt(new Date(body[t].ts).getTime() / 1000)
             });
           }
@@ -91,15 +91,15 @@ function get_orders(coin, exchange, api_error_msg, cb) {
 
         for (let b = 0; b < body.bids.length; b += 2) {
           buys.push({
-            price: parseFloat(body.bids[b]),
-            quantity: parseFloat(body.bids[b + 1])
+            price: parseFloat(body.bids[b]) || 0,
+            quantity: parseFloat(body.bids[b + 1]) || 0
           });
         }
 
         for (let s = 0; s < body.asks.length; s += 2) {
           sells.push({
-            price: parseFloat(body.asks[s]),
-            quantity: parseFloat(body.asks[s + 1])
+            price: parseFloat(body.asks[s]) || 0,
+            quantity: parseFloat(body.asks[s + 1]) || 0
           });
         }
 
@@ -132,10 +132,10 @@ function get_chartdata(coin, exchange, api_error_msg, cb) {
           for (let c = 0; c < body.length; c++)
             chartdata.push([
               parseInt(body[c][9]),
-              parseFloat(body[c][2]),
-              parseFloat(body[c][1]),
-              parseFloat(body[c][0]),
-              parseFloat(body[c][3])
+              parseFloat(body[c][2]) || 0,
+              parseFloat(body[c][1]) || 0,
+              parseFloat(body[c][0]) || 0,
+              parseFloat(body[c][3]) || 0
             ]);
 
           return cb(null, chartdata);
diff --git a/lib/markets/southxchange.js b/lib/markets/southxchange.js
index a29d6fb..794832b 100644
--- a/lib/markets/southxchange.js
+++ b/lib/markets/southxchange.js
@@ -21,11 +21,11 @@ function get_summary(coin, exchange, api_error_msg, cb) {
       else {
         try {
           const summary = {
-            'volume': parseFloat(body.Volume24Hr),
-            'bid': parseFloat(body.Bid),
-            'ask': parseFloat(body.Ask),
-            'last': parseFloat(body.Last),
-            'change': parseFloat(body.Variation24Hr)
+            'volume': parseFloat(body.Volume24Hr) || 0,
+            'bid': parseFloat(body.Bid) || 0,
+            'ask': parseFloat(body.Ask) || 0,
+            'last': parseFloat(body.Last) || 0,
+            'change': parseFloat(body.Variation24Hr) || 0
           };
 
           return cb(null, summary);
@@ -56,8 +56,8 @@ function get_trades(coin, exchange, api_error_msg, cb) {
           for (let t = 0; t < body.length; t++) {
             trades.push({
               ordertype: body[t].Type,
-              price: parseFloat(body[t].Price),
-              quantity: parseFloat(body[t].Amount),
+              price: parseFloat(body[t].Price) || 0,
+              quantity: parseFloat(body[t].Amount) || 0,
               timestamp: parseInt(body[t].At)
             });
           }
@@ -89,15 +89,15 @@ function get_orders(coin, exchange, api_error_msg, cb) {
 
         for (let b = 0; b < body.BuyOrders.length; b++) {
           buys.push({
-            price: parseFloat(body.BuyOrders[b].Price),
-            quantity: parseFloat(body.BuyOrders[b].Amount)
+            price: parseFloat(body.BuyOrders[b].Price) || 0,
+            quantity: parseFloat(body.BuyOrders[b].Amount) || 0
           });
         }
 
         for (let s = 0; s < body.SellOrders.length; s++) {
           sells.push({
-            price: parseFloat(body.SellOrders[s].Price),
-            quantity: parseFloat(body.SellOrders[s].Amount)
+            price: parseFloat(body.SellOrders[s].Price) || 0,
+            quantity: parseFloat(body.SellOrders[s].Amount) || 0
           });
         }
 
@@ -132,10 +132,10 @@ function get_chartdata(coin, exchange, api_error_msg, cb) {
             if ((c % 3) == 0)
               chartdata.push([
                 parseInt(new Date(body[c].Date.toString() + 'Z').getTime()),
-                parseFloat(body[c].PriceOpen),
-                parseFloat(body[c].PriceHigh),
-                parseFloat(body[c].PriceLow),
-                parseFloat(body[c].PriceClose)
+                parseFloat(body[c].PriceOpen) || 0,
+                parseFloat(body[c].PriceHigh) || 0,
+                parseFloat(body[c].PriceLow) || 0,
+                parseFloat(body[c].PriceClose) || 0
               ]);
           }
 
diff --git a/lib/markets/xeggex.js b/lib/markets/xeggex.js
index db71208..8e8907f 100644
--- a/lib/markets/xeggex.js
+++ b/lib/markets/xeggex.js
@@ -21,15 +21,15 @@ function get_summary(coin, exchange, api_error_msg, cb) {
       else {
         try {
           const summary = {
-            'high': parseFloat(body.highPriceNumber),
-            'low': parseFloat(body.lowPriceNumber),
-            'volume': parseFloat(body.volumeNumber),
-            'volume_btc': parseFloat(body.volumeUsdNumber),
-            'bid': parseFloat(body.bestBidNumber),
-            'ask': parseFloat(body.bestAskNumber),
-            'last': parseFloat(body.lastPriceNumber),
-            'prev': parseFloat(body.yesterdayPriceNumber),
-            'change': parseFloat(body.changePercentNumber)
+            'high': parseFloat(body.highPriceNumber) || 0,
+            'low': parseFloat(body.lowPriceNumber) || 0,
+            'volume': parseFloat(body.volumeNumber) || 0,
+            'volume_btc': parseFloat(body.volumeUsdNumber) || 0,
+            'bid': parseFloat(body.bestBidNumber) || 0,
+            'ask': parseFloat(body.bestAskNumber) || 0,
+            'last': parseFloat(body.lastPriceNumber) || 0,
+            'prev': parseFloat(body.yesterdayPriceNumber) || 0,
+            'change': parseFloat(body.changePercentNumber) || 0
           };
 
           return cb(null, summary);
@@ -60,8 +60,8 @@ function get_trades(coin, exchange, api_error_msg, cb) {
           for (let t = 0; t < body.length; t++) {
             trades.push({
               ordertype: body[t].type,
-              price: parseFloat(body[t].price),
-              quantity: parseFloat(body[t].base_volume),
+              price: parseFloat(body[t].price) || 0,
+              quantity: parseFloat(body[t].base_volume) || 0,
               timestamp: parseInt(new Date(body[t].trade_timestamp).getTime() / 1000)
             });
           }
@@ -93,15 +93,15 @@ function get_orders(coin, exchange, api_error_msg, cb) {
 
         for (let b = 0; b < body.bids.length; b++) {
           buys.push({
-            price: parseFloat(body.bids[b].numberprice),
-            quantity: parseFloat(body.bids[b].quantity)
+            price: parseFloat(body.bids[b].numberprice) || 0,
+            quantity: parseFloat(body.bids[b].quantity) || 0
           });
         }
 
         for (let s = 0; s < body.asks.length; s++) {
           sells.push({
-            price: parseFloat(body.asks[s].numberprice),
-            quantity: parseFloat(body.asks[s].quantity)
+            price: parseFloat(body.asks[s].numberprice) || 0,
+            quantity: parseFloat(body.asks[s].quantity) || 0
           });
         }
 
diff --git a/lib/markets/yobit.js b/lib/markets/yobit.js
index 89d83b5..afc6107 100644
--- a/lib/markets/yobit.js
+++ b/lib/markets/yobit.js
@@ -22,12 +22,12 @@ function get_summary(coin, exchange, api_error_msg, cb) {
         try {
           const prefix = body[coin + '_' + exchange];
           const summary = {
-            'high': parseFloat(prefix.high),
-            'low': parseFloat(prefix.low),
-            'volume': parseFloat(prefix.vol),
-            'bid': parseFloat(prefix.buy),
-            'ask': parseFloat(prefix.sell),
-            'last': parseFloat(prefix.last)
+            'high': parseFloat(prefix.high) || 0,
+            'low': parseFloat(prefix.low) || 0,
+            'volume': parseFloat(prefix.vol) || 0,
+            'bid': parseFloat(prefix.buy) || 0,
+            'ask': parseFloat(prefix.sell) || 0,
+            'last': parseFloat(prefix.last) || 0
           };
 
           return cb(null, summary);
@@ -59,8 +59,8 @@ function get_trades(coin, exchange, api_error_msg, cb) {
           for (let t = 0; t < prefix.length; t++) {
             trades.push({
               ordertype: (prefix[t].type.toLowerCase() == 'bid' ? 'BUY' : 'SELL'),
-              price: parseFloat(prefix[t].price),
-              quantity: parseFloat(prefix[t].amount),
+              price: parseFloat(prefix[t].price) || 0,
+              quantity: parseFloat(prefix[t].amount) || 0,
               timestamp: parseInt(prefix[t].timestamp)
             });
           }
@@ -93,15 +93,15 @@ function get_orders(coin, exchange, api_error_msg, cb) {
 
         for (let b = 0; b < prefix.bids.length; b++) {
           buys.push({
-            price: parseFloat(prefix.bids[b][0]),
-            quantity: parseFloat(prefix.bids[b][1])
+            price: parseFloat(prefix.bids[b][0]) || 0,
+            quantity: parseFloat(prefix.bids[b][1]) || 0
           });
         }
 
         for (let s = 0; s < prefix.asks.length; s++) {
           sells.push({
-            price: parseFloat(prefix.asks[s][0]),
-            quantity: parseFloat(prefix.asks[s][1])
+            price: parseFloat(prefix.asks[s][0]) || 0,
+            quantity: parseFloat(prefix.asks[s][1]) || 0
           });
         }