chart with KG and MB in Y -axis

Hi, I'm facing issue with chart which displays KG and MB, where MB are bigger by the number, and it shows wrong chart: Green line needs to be above. event examples: Heap: 13.2G Heap: 6208.6M How make, that MB are down in the chart? ![alt text][1] [1]: /storage/temp/274518-chart2.jpg My search: ` | rex Heap:\s(?\d+\.\d)\w | search HeapNum!=" " | eval critical=15 | table _time HeapNum critical `