that is a cool idea, and as a BitcoinHolder i am all for these kinds of long term stuff.
and i don't want to disappoint you or anything but what you are storing is already available online
![Roll Eyes](https://bitcointalk.org/Smileys/default/rolleyes.gif)
for example you can visit any exchange that gives you historic data and use that to draw a line chart or even like poloniex get the OHLC data and draw an OHLC chart.
example for XMR from their API doc:
https://poloniex.com/public?command=returnChartData¤cyPair=BTC_XMR&start=1405699200&end=9999999999&period=14400there is also bitcoinity where you can get
market cap or
price and other stuff in CSV format (only for bitcoin though).