Because of the initial pricing system, I have gotten a fair bit more than 50% of the collateral back on my conversions.
The way to make the chart show how much was actually converted would be based on the fill_collaterallized_convert vop after it finishes - the amount_in is how much Hive is actually converted in the end.
Readers should keep in mind 3.5 day lag compared to the convert transactions that created them.