Conditional weighted average

[Charles Bushby]

Would anyone know how to work out the weighted average P Year based on the Area field for any given Species in the table below where Land Use can be either High Forest or Windblow and Forecast can only be F?

I can do this with sumproduct but am not sure how to have more than one allowable option in the Land Use field i.e. High Forest or Windblow


Area Land Use Species P year Forecast
10.00 High Forest SS 1995 F
5.00 High Forest LP 2000 F
200.00 Windblow SS 1950 F
4.00 High Forest NS 1968 F
30.00 Replanting SS 2019 F
4.00 High Forest MB 1850 N

If anyone can help I would be most obliged.

Charles

 

[oldbrewer]

can you define weighted average, please ?

 

[barry houdini]

Hello Charles, try as follows for Species = "SS":

=SUMPRODUCT((Species="SS")*((LandUse="High Forest")+(LandUse="Windblow"))*(Forecast="F"),Area,PYear)/SUMPRODUCT((Species="SS")*((LandUse="High Forest")+(LandUse="Windblow"))*(Forecast="F"),Area)

Note + instead of * gives you an "OR" for the Landuse Category

This gives me 1952.14

 

[Charles Bushby]

Hi Barry,

That worked perfectly so thank you very much for helping me out.

Charles

 

[Charles Bushby]

Hi Old Brewer,

It is similar to a normal average but one can weight the average with data from another field. If you do a search on the internet for weighted averages you will find a lot of information that defines it very well.

Charles

 

[oldbrewer]

thanks, Charles.