There are several potential reasons investors are shrugging off the drop in oil prices, reports Bloomberg.

During the most recent previous bear markets for oil, they were coupled with a slowdown in demand from China.

Another simple factor is that the bear market which ended last year wiped out a lot of energy companies’ valuation, shrinking it down to less than 6% of the S&P 500, versus 11% three years ago, according to Bloomberg.

There is also less systemic risk associated with the lower prices now. The correlation between the high-yield bond market and crude has fallen to 0.32, versus a peak of 0.87 in early 2016.

“The backdrop for oil prices is very different,” Sean Darby of Jefferies Hong Kong wrote in a report Thursday. “There has been significant improvement in balance sheet repair in 2016 through capital raisings while many producers hedged production as oil prices rose.”