index - a numerical scale used to compare variables with one another or with some reference number. 1  margin of error, margin of safety, safety margin - the margin required in order to insure safety; in engineering the margin of safety is the strength of the material minus the anticipated stress.
Nutty Ways to Celebrate Squirrel Appreciation Day This Year. SQUIRRELS! Whether you love them or loathe them, National Squirrel Appreciation Day, January 21st, is a great time to take a few moments and learn about these nutty animals. If you count flying squirrels we have 10 tree species in North America.
Appreciation Day is the third episode in Season 2 (and fifteenth episode overall) of Regular Show. It first aired on January 10, 2011. Mordecai and Rigby decide to write fraudulent statements in Benson's book of park records, but trouble ensues when the listed events happen for real.