Where Does the '50% of Picking Time Is Travel' Statistic Actually Come From?

Answer first

The statistic that travel is roughly half of an order picker's time does not come from a study. It traces to a single source: Edward Frazelle's book World-Class Warehousing, published in 1996 through his own consultancy, Logistics Resources International. No sample size, methodology, or facility count has ever been disclosed behind the figure. It is a respected practitioner's estimate that the industry has repeated for nearly thirty years as though it were research.

The number everyone quotes

If you have read anything about warehouse efficiency, you have seen some version of it. Travel is 50 percent of picking time. Or 55 percent. Sometimes it is dressed up as a breakdown: traveling 55 percent, searching 15 percent, extracting 10 percent, paperwork 20 percent. Vendors cite it. Consultants cite it. Trade journalists cite it. It is the load-bearing statistic under a whole category of software.

It is also, as far as anyone can trace, a single consultant's figure.

Walking the citation chain

Here is where it actually leads, step by step, because the point of this page is to show the work rather than assert a conclusion.

The most common academic-looking source for the figure is Bartholdi and Hackman's Warehouse & Distribution Science, a free textbook from Georgia Tech that is genuinely well regarded. It gives the familiar breakdown, with travel as the largest share.

But the textbook does not present that breakdown as its own finding. It cites it, to a reference. Follow the reference and it resolves to: E. H. Frazelle, World-Class Warehousing, Logistics Resources International, Atlanta, 1996.

Logistics Resources International was Frazelle's own consultancy. The book is, in effect, self-published. And nowhere in the chain, not in the textbook and not in the book's own presentation of the number, is there a disclosed dataset, a sample size, a methodology, or a count of the warehouses it was drawn from.

So the industry's most-repeated warehouse statistic is a consultant's estimate from a 1996 book, given the appearance of rigour by an academic text that cites it.

The tell

There is a phrase that gives it away. In trade coverage, the figure is almost always introduced with something like "it is generally accepted that roughly half of picking time is travel."

"Generally accepted" is what people write when there is no study to point to. If there were a dataset, they would name it.

Is the number wrong?

Probably not, and this is the honest part. Travel really is a large part of a picker's day, and the direction of the claim matches what anyone who has watched a pick operation would expect. We use the figure ourselves, carefully.

The problem is not the number. The problem is precision it does not have. "Roughly half" is a reasonable rule of thumb. It is not "studies show that 55 percent." If you are building a business case, or evaluating a vendor's promised savings, you should know which kind of number you are standing on. A rule of thumb is fine as a starting point. It is not evidence.

What to measure instead

Warehouse professionals are not actually scored on travel time. It does not appear in WERC's DC Measures, the benchmark most distribution operations report against. The number on their scorecard is lines picked and shipped per person hour.

That is the number worth improving, and unlike the travel statistic, it is one you can measure precisely in your own building from data you already have. You do not need a rule of thumb to tell you what your pickers are getting done. You need your own order history.

The honest takeaway

Be careful with borrowed numbers, especially the famous ones. The most quoted statistic in warehousing turns out to rest on a single self-published estimate. That does not make it useless, but it does mean that any vendor quoting a precise savings percentage derived from it is building precision on top of a guess. Ask where their number came from. The answer is usually the same place this one did.