long PX supply that deterred PX price from rising with feedstock naphtha

PX-naphtha spread has been shrinking since this March. It narrowed to around $300/mt in Sep, and further to $275/mt in Oct. It hovered around $260-270/mt in the first half of Nov, however, the spread reduced drastically in recent days to $236/mt as of Nov 25 and further to $228/mt on Nov 26, close to the low point of $221/mt in 2014 (PX-naphtha spread was below $235/mt for 6 trading days in total in 2014).

It seems that it was firmer naphtha that crushed PX-naphtha spread. In Nov, naphtha price rose by nearly 10%, while PX price was largely stable. However, if we take a deeper look, it was long PX supply that deterred PX price from rising with feedstock naphtha.