from grapho- + -oil + -logie-logy: inference of future production from an oil production profile. The theory underlying graphoilogy is that production profile is an expression of limited oil reserves; hence, a systematic analysis of the way production profiles are shaped can reveal traits of actual ressources.
The fall in Vehicle-Miles driven is unprecedented, no wonder crude oil is piling up in inventories. In the monthly data, It seems that there is a beginning of recovery so maybe prices will go back up at the end of the year.