Ethylene is the production of plastic raw materials, plastic and vinyl spreads can be roughly as plastic production enterprise gross profit. When the price difference is very small or even negative, plastic production enterprise profits will be diluted, so this kind of plastic and vinyl small gap phenomenon is very difficult to maintain for a long time.

We import price of ethylene with northeast Asia x middle price by 1.17 yuan against the dollar (VAT) x 1.05 (tariffs) + 150 yuan/ton (freight) calculate the imported ethylene discount the price of the yuan, get ethylene conversion price compared with plastic spot price found that since 2007, the gap between the maximum value of 5533 yuan/ton, minimum value is - 289 yuan/ton, the average is 1677 yuan/ton. And as of March 20, plastic and ethylene price is 986 yuan/ton, for the first time since October 17, 2014, both price below 1000 yuan/ton. As the plastic and vinyl spreads narrowed, plastic production enterprise profit decline, unless ethylene prices fall sharply, otherwise the plastic price up to down.