- What is the difference between HARMEAN and AVERAGE?
- HARMEAN calculates the average of reciprocals (1/x), making it ideal for rates and ratios. AVERAGE sums values and divides by count, treating all numbers equally. HARMEAN is mathematically correct when you're averaging rates where low values deserve more influence—for example, budget efficiency ratios or speed averages.
- Why does HARMEAN give a different result than the arithmetic average?
- HARMEAN uses reciprocals in its calculation, so it inherently produces a smaller or equal value. This is intentional—it properly weights rate data. For example, averaging speeds of 60 mph one way and 30 mph back is 40 mph by harmonic mean, not 45 mph, because you spend twice as long at the slower speed.
- What happens if my data includes zero or negative values?
- HARMEAN will return #DIV/0! error because the function requires all values to be strictly positive (> 0). To handle negative variance data, use ABS() to convert to absolute values: =HARMEAN(ABS(B2:B10)). You cannot include zero or negative numbers in any form.
- Can I use HARMEAN with a range or array formula?
- Yes. You can use a range like =HARMEAN(A1:A10), individual cells like =HARMEAN(A1, B1, C1), or array operations like =HARMEAN(A1:A5/B1:B5). HARMEAN accepts 1 to 255 arguments total. Using more values produces a more representative harmonic mean.