Grand Exchange Portfolio - Price history (suggestion)

Hi,
I don't seem to know any tools that are currently available, outside of rsbandb, to quickly follow GE price trends.

Yet it could have some specific improvements.

Problem: lower valued items are undermined by higher valued items, therefore seeing low value item price change on a graph is not practical.
Example: runes can cost 17 gp or 2000 gp. Any price change of 17 gp rune would be presented as a "flat-line".

Possible solution:

Graph % change of item gp value and allow to switch between the different graph modes.

Thank you for this idea. The GE portfolios are something that never left beta stage and need to be revised. I hope to get to that soon.