Why do sites like cryptocompare show a wrong Chng Since ICO %?

[nndep3m]

Looking here: https://www.cryptocompare.com/ico/#/completed

A lot of the Chng Since ICO % is very high. For instance recently PRIX is showing 1000%+ change, and QVT 4000%+ chng. Yet both of these are trading more or less at their ICO price on etherdelta. Why are these wrong amounts being shown? And is there a site that will show actual reliable Chng Since ICO % that I can also sort by date?

[UnlimitedMoneymaker]

I have been searching for this too but I didn't find best option. Most of these sites limited in options and thier info often is wrong or not accurate.
For example
https://icostats.com/roi-since-ico
too limited so few ICOs are listed here.

http://icorating.com/
It is better but not the all information provided

https://icotracker.net/
Is ok too