Gasoline prices through Monday, vs. Brent. Why the divergence?

Both prices are depicted using log scales. It’s clear it’s not a one-for-one relationship, but the gap is interesting. I don’t know if this is the reason, but the gasoline (and distillates) stocks are way down (for week ending 5/22).

Figure 2: Gasoline stocks end-of week, Mbbls, n.s.a. (blue). Source: EIA. 

I’ve drawn year to year trends, since the data are not seasonally adjusted.