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True. Regardless, DSR not being completely valid due to discrepancies in Sunday selling does not make comparisons based on monthly sales volume any more valid. As long as auto makers are consistent in their own ways of sales reporting I don't see a problem.
The problem lies in the comparison of numbers. We say X mfg is up .1% and Y mfg is down 5% - yet both are reported using different formulas!!!!
That's not good and can not be compared.
I honestly think the best way to do it is based on true monthly sales volume.
The problem lies in the comparison of numbers. We say X mfg is up .1% and Y mfg is down 5% - yet both are reported using different formulas!!!!
That's not good and can not be compared.
Yes, they need to be normalized based on the same formula first before a valid comparison between different manufacturers can be made.
I honestly think the best way to do it is based on true monthly sales volume.
When we analyze sales trend to see if there is a "slowdown" in sales or if the sales is picking up, we want volume to be the dividend, and time to be the divisor. The problem with "monthly sales volume" using (volume / month) with month as a divisor is simply that "month" is not a good time unit to begin with. Not only do different months vary in number of days, but in terms of car selling the same month can also vary in number of selling days from year to year, resulting in a varying divisor. How can the result be meaningful when both the dividend and the divisor are variable? You tell me.
Not only do different months vary in number of days, but in terms of car selling the same month can also vary in number of selling days from year to year, resulting in a varying divisor. How can the result be meaningful when both the dividend and the divisor are variable? You tell me.
I would argue that the "selling days" which I think we can agree does not exist as a whole number could be eliminated and the results would wash out (the percentage drop this month would be made up the following month).
05-04-07, 07:01 PM
