I'm just looking at trying to do that myself because I was curious, is there a way to show it as % of ath as I'm just getting a flat line for the S&P on my phone when trying to compare it to bitcoin.
Can you expound more on what you mean b y displaying it as % of ath?
You're going to get a slow and steady upward line(that sure does look quite flat) on the S&P500 as it's really not THAT volatile(compared to bitcoin at least).
Here's a 1 year chart of BTC/USD via Coinbase vs the SPDR S&P 500 ETF; with bitcoin being orange and the SPY being blue:
And yes, it's going to look A LOT flatter when viewing the 5 year chart, because the SPY doesn't have those huge price spikes like bitcoin has.