Source Historical Coin Prices
For those of you that want access to historical cryptocoin prices, check out coinmarketcap.com. To access the histrical data ...
1 click on a currency name (see a partial list above)
2 scroll down to tabs (see image below) (charts, markets, social, tools & historical data)
3 click the historical data link
4 check the date range, if not adequate, click the date range box on the right (see the 2nd image below)
5 in order to download, you will have to do a copy and paste operation into a text file.
I just did this myself for the date range Jan 1, 2017 to June 26, 2017 for three coins, bitcoin, ethereum and litecoin. In all three cases the text files were imported easily into an Excel compatible spreadsheet on an Android tablet.
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how far back does it go
I checked bitcoin & litecoin and in both cases got Apr 28, 2013.