In addition, these factors led to more aggressive PVC contracting positions for 2012. The net result was a significant downward pressure on PVC pricing in the fourth quarter, squeezing margins more than expected. These price drops played out in both the domestic and export markets. This $0.03 per pound price increase we have seen in January reflects PVC producers' desire to get some positive margin back in that business. In addition to the factors I have outlined, we did experience an unplanned outage in our Plaquemine site in late December that resulted in a loss of about 16,000 ECUs across the fourth quarter of 2011 and first quarter of 2012.
Reflecting back on the total year, the operational issues at Plaquemine and specifically our chloralkali unit are not acceptable in the future. Even though our chloralkali unit ran at higher operating rate than the industry in the fourth quarter of 2011, we target for those units to run more consistently than the results demonstrate for the past year.
During the year, we were approximately 11% below target for annual capacity operating rate. While some of these issues were the result of uncontrollable forces such as the Mississippi River flooding and other natural causes, others are correctable, and we intend to substantially improve the reliability of this plant for the controllable items.