Merge pull request cs50#355 from cs50/finance19

update finance

Author: dmalan

_pages/2019/x/psets/8/finance/finance.adoc

@@ -17,7 +17,57 @@ If you're not quite sure what it means to buy and sell stocks (i.e., shares of a
 
 You're about to implement C$50 Finance, a web app via which you can manage portfolios of stocks. Not only will this tool allow you to check real stocks' actual prices and portfolios' values, it will also let you buy (okay, "buy") and sell (okay, "sell") stocks by querying https://iextrading.com/developer/[IEX] for stocks' prices.
 
-Indeed, IEX lets you download stock quotes via their API (application programming interface) using URLs like https://api.iextrading.com/1.0/stock/NFLX/quote. Notice how Netflix's symbol (NFLX) is embedded in this URL; that's how IEX knows whose data to return. If you follow that link, you'll see a reponse in JSON (JavaScript Object Notation) format. It's a bit messy, but notice how, between the curly braces, there's a comma-separated list of key-value pairs, with a colon separating each key from its value.
+Indeed, IEX lets you download stock quotes via their API (application programming interface) using URLs like `https://cloud-sse.iexapis.com/stable/stock/nflx/quote?token=API_KEY`. Notice how Netflix's symbol (NFLX) is embedded in this URL; that's how IEX knows whose data to return. That link won't actually return any data because IEX requires you to use an API key (more about that in a bit), but if it did, you'd see a response in JSON (JavaScript Object Notation) format like this:  
+
+[source,json]
+----
+{  
+   "symbol": "NFLX",
+   "companyName": "Netflix, Inc.",
+   "primaryExchange": "NASDAQ",
+   "calculationPrice": "close",
+   "open": 317.49,
+   "openTime": 1564752600327,
+   "close": 318.83,
+   "closeTime": 1564776000616,
+   "high": 319.41,
+   "low": 311.8,
+   "latestPrice": 318.83,
+   "latestSource": "Close",
+   "latestTime": "August 2, 2019",
+   "latestUpdate": 1564776000616,
+   "latestVolume": 6232279,
+   "iexRealtimePrice": null,
+   "iexRealtimeSize": null,
+   "iexLastUpdated": null,
+   "delayedPrice": 318.83,
+   "delayedPriceTime": 1564776000616,
+   "extendedPrice": 319.37,
+   "extendedChange": 0.54,
+   "extendedChangePercent": 0.00169,
+   "extendedPriceTime": 1564876784244,
+   "previousClose": 319.5,
+   "previousVolume": 6563156,
+   "change": -0.67,
+   "changePercent": -0.0021,
+   "volume": 6232279,
+   "iexMarketPercent": null,
+   "iexVolume": null,
+   "avgTotalVolume": 7998833,
+   "iexBidPrice": null,
+   "iexBidSize": null,
+   "iexAskPrice": null,
+   "iexAskSize": null,
+   "marketCap": 139594933050,
+   "peRatio": 120.77,
+   "week52High": 386.79,
+   "week52Low": 231.23,
+   "ytdChange": 0.18907500000000002,
+   "lastTradeTime": 1564776000616
+}
+----
+
+Notice how, between the curly braces, there's a comma-separated list of key-value pairs, with a colon separating each key from its value.
 
 Let's turn our attention now to this problem's distribution code!