Text: Lake Powell
In the year 1999, the surface elevation of Lake Powell was 3806 feet above sea level. In the year 2006, the surface elevation of Lake Powell was 3264.9 feet above sea level.
Interpret the rate of change in this situation.
The surface elevation of Lake Powell is [increasing] [decreasing] at a rate of [feet every 7 years] [feet years] [feet per year].