when BitUSD/BTS decreases

[legend018]

I think I might be looking at the wrong graph. It's hard to know what graphs to actually concentrate on with all this.
For example I have found bts to usd charts, bitusd-bts charts and BTS to bitusd charts.  When shorting, which one do I actually concentrate on watching?  The BITUSD-BITUSD to BTS showing  1.107105 below? 

BTS to USD is 0.8124 which is shown:
https://www.finder.com/bitshares

BTS to USD 0.837870 seen here:
https://currencio.co/bts/

also on currencio.co
BITUSD-BITUSD to BTS is 1.107105

BTS to bitusd is 0.903257

[legend018]

When I read about doing a short on a bitasset there are some discussions online that talks about when BitUSD/BTS decreases (dollar has declined in relateive value to BTS) - which would be when you short I guess.

Anyway: If bitshares is doing well and continues to do well, then wouldn't that mean it would be impossible to short since the dollar value is constantly increased? Or am I reading this all wrong or not understanding. I'm using this graph. https://www.finder.com/bitshares