What is the most important metric in retail? And the answer is NOT that ‘it depends’.



Whilst I like GMROI as being most useful and revealing, it has one drawback in that there aren’t many benchmarks available to be used. Its ugly sister metric, stockturn, is simpler but still extremely useful – AND importantly it goes to the heart of retailing. (Breaking bulk to tailor product/quantity to the needs of the consumer.)

Understanding the stockturn of a product/category is extremely useful, yet so few small retailers actually do the homework necessary to have access to this metric. (Services and hospitality would have equivalent metrics that go by different labels, but the same principle applies.)

Your stockturn will reveal that:

(1) Your inventory levels are wrong, or that

(2) Your sales rate is wrong.

But there is one feature or principle of stockturn that even very experienced retailers don’t know and don’t appreciate. The ideal/optimum stockturn for a category is (for practical purposes and in most cases) fixed. That is the optimum stockturn for any given category is a given.

With metrics like sales or profit, there is never a case of ‘having too much’. But with stockturn there is an optimum range. Consider these examples.

The stockturn for a daily newspaper is 365 times per annum. Any more than that would indicate inefficient double handling and any less would mean you probably overstock.

Fashion has a stockturn of 4 times per year – for the obvious reason that the purchase cycle is driven by the seasons. The Christmas Tree Farm sells its stock once a year.

The same applies for every category or product. This rate is determined by (a) the retailers’ business models and (b) by how consumers purchase certain products.

Good planning and good systems will allow efficient retailers to make mid-season corrections on their stock and instead of turning their stock once per season, they may be able to do a mid-season clearance of the duds and stock up on the best sellers. They may turn their stock 1.5 x per season, resulting in a turn of 6x per annum. Inefficient retailers (like Department Stores) who also sell fashion traditionally achieve stockturns of less than 4x per season in their fashion category.

The vast majority of (specialty) fashion retailers will sit in that 3.5 – 6.5 range. But there are ‘fast fashion’ retailers who have a different business model. For instance, Zara is vertically integrated and goes from runway to store in a few weeks. They achieve stockturns of 17x per annum (my estimate.) But then, they are not really in the Fashion business, they are in the disposable clothing business.

What people don’t appreciate is that there is an optimum level for this metric. Just like your heartbeat can’t be in the 1-25 bpm range, nor can it sustain 200+bpm. To work best it needs to be in the 65-75 range.

That is just for a human being. Canaries’ hearts flutter at 1000 bpm, a duck at 190 and a horse at 38. (Yes, there is an apparent mass/ rate inversion – just like the boutique and the department store.)