Retailers are spending less on loss prevention, and maybe that’s not such a good idea. In 2016, the rate of “shrinkage,” or inventory that goes missing for any reason, increased to 1.44% of all sales, or a total of almost $48.9 billion.

Where did that stuff go? According to the annual National Retail Security Survey from trade group the National Retail Federation, the largest share of missing merch is taken by shoplifters, ranging from the most petty thieves to organized crime rings that steal in mass quantities and re-sell what they take. Almost 7% of shrinkage just gets a great big “shrug,” since loss prevention professionals don’t know where it goes.

Here’s the breakdown:

Shoplifting/external (includes organized crime) = 36.5%
Employee theft/internal = 30%
Administrative and paperwork error = 21.3%
Vendor fraud or error = 5.4%
Unknown loss = 6.8%

This year, the survey also asked about return fraud for the first time, and the loss prevention executives said that the average amount lost to it is $1,766.27. Incidentally, The Retail Equation, the company that keeps a database of shoppers who return purchases excessively by having stores scan customers’ driver’s licenses, sponsored this year’s survey.

The loss prevention executives’ conclusion, predictably, was that stores should spend more on loss prevention.

“Retail executives need to realize that money spent on preventing losses is money that improves the bottom line,” Bob Moraca, Vice President of Loss Prevention at the NRF, said in a statement.

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