Here's the logic behind General Motors' decision to stop reporting monthly sales figures and instead sprinkle out the data on a quarterly basis: 30 days "is not enough time to separate real sales trends from short-term fluctuations," GM says, and quarterly reporting "will make it easier to see how the business is performing."
It won't make it any easier. Trust us.
True, year-on-year comparisons are often distorted. A manufacturer may be ramping up or phasing out a key product.
Weather can be an issue, there's seasonal stuff to consider, incentives are a factor and the number of selling days varies from month to month.
So we get the idea, but we question the motivation, and we hate the decision. It signals a growing lack of transparency that we fear will become the industry norm. It's a misguided move GM ought to reconsider. There is no reason compelling enough to withhold vital information from dealer and supplier partners — not to mention the wider world GM operates in.
The reasons the company cites are the same it used when it stopped reporting monthly production figures five years ago — and when it ended 10-day sales reports in 1994, a movement Chrysler began in 1991.
When 10-day reports went away, those who relied on the numbers had to develop other sources of the midmonth sales data, most of which are estimates based on data samples.
But dealers must be able to track the performance of brands they represent. Suppliers struggle with the eternal problem of unreliable sales and production forecasts from manufacturers, and cutting out monthly sales reports adds to that struggle.
GM ought to keep these and other stakeholders in mind. The numbers are used by forecasters, economists, analysts, investors and others, including government bureaucrats making decisions that affect the entire U.S. economy.
GM may have determined that no amount of sales-day spin penetrates the media and the mind of Wall Street.
But if the company doesn't believe outsiders can grasp the nuances of its business, it should do a better job of explaining. As it now stands, GM will increase the influence of analysts' extrapolation and inflate the importance of the anecdotal.