# Greenhouse Gas Statistical Function Definitions

**Easy to Use!**

Statistical functions are easy to use. Just click on the box for the statistics you want to see. The database will automatically calculate the statistical value (sum, count, max, min, etc.) for the other columns (which taken together comprise a statistical group) that you have selected. This may be a difficult concept to understand but it is easily illustrated in the examples below.

## Statistical Function Definitions

**SUM**

This function gives you the sum of the selected variable (usually release estimate) for each unique "group" value. If you selected city, state, and the "Sum Function for Release Estimate", then a "Release Estimate Sum" will be reported for each unique combination of city and state.

**AVERAGE**

This function gives you the arithmetic mean of the selected statistical variable for each unique "group" value. This is computed by taking sum of the group and dividing it by the number of individual rows in the group.

**COUNT**

This function gives you the total number of individual rows for each unique "group" value. Selecting this gives you a good indication of how many rows resulted from your selection criteria. If all the counts are 1, then you have selected variables that resulted in the group value and the single number value being the same, giving you a meaningless group value.

**MAX**

This function gives you the highest value in the group.

**MIN**

This function gives you the lowest value in the group. It ignores null values.

**STANDARD DEVIATION**

This function gives you the deviation from the average or the mean. This allows you to determine whether certain row values are out of proportion to the others, giving you an average that is much higher than the mean.

**VARIANCE**

This function gives you the variance of all values for a group of rows.