Our system was tested by weather extremes in 2010, but fortunately they were normal by our standards. An unusually cold winter and hot summer across our service territory pushed demand up and required all available units to be operational.

Our peak demands are highest during the cooling season. In 2010, cooling degree days were up 17 percent throughout the AEP system compared with 2009. By contrast, heating degree days were up only 9 percent. Cooling degree days are the number of degrees that a day’s average temperature is above 65 degrees Fahrenheit, prompting greater use of air conditioning. The one exception is Texas, where the measure is 70 degrees. Each degree above this temperature results in an additional cooling degree day. The same is true in reverse for heating degree days.

The duration and frequency of power outages are basic reliability measures that we track continuously. Our performance in 2010 was very good in two of three metrics we track.

The first is the System Average Interruption Duration Index (SAIDI), which measures the average length of time a customer is without power during an outage. The three-year average (2008-2010) improved 1.7 percent over the previous three-year rolling average (2007-2009). In 2010, our three-year SAIDI average was 194.7 minutes -- our best performance in five years. The improvement can be traced to better maintenance in circuit sections of the system with high customer density/counts, also known as feeder breaker zones, and more effective use of approved tree trimming procedures. Approximately 30 percent of SAIDI is caused by tree limbs falling on or getting tangled in power lines.

The second key reliability metric is the System Average Interruption Frequency Index (SAIFI), which represents the average number of interruptions experienced by a customer. At the end of 2010, the three-year rolling average of SAIFI was 1.397 compared with 1.471 in 2009, an improvement of 5 percent. This also was our best performance in five years.

The third metric is the Customer Average Interruption Duration Index (CAIDI), which represents the average length of time to restore service once an outage occurs. Our performance of this measure did not meet our expectations as CAIDI increased nearly 3.5 percent in 2010 compared with the 2009 three-year rolling average. CAIDI was negatively impacted by the work force restructuring. We will continue to monitor our performance and staffing levels very closely.