How is the Ivey Purchasing Managers Index calculated?
The Ivey Purchasing Managers Index is based on month to month changes in dollars of purchases. It is calculated by categorizing the survey responses into percentages of higher than, the same at, or lower than the previous month. The difference between the higher and lower percentages, either positive or negative, is divided by two. The resulting number is added to or subtracted from 50 to give the monthly index number. An Ivey Purchasing Managers Index of 50 indicates no change from the previous month. An Ivey Purchasing Managers Index above 50 shows an increase while an index below 50 indicates a decrease. Similar calculations are done for employment, inventories, supplier deliveries and prices. No seasonal, inflation or other adjustments are made to the data or the calculations.
