The nationwide baby formula shortage is getting worse

Baby formula is getting even harder to come by at retailers across the U.S., amid a nationwide shortage of one of the most important products for new parents. 

At retailers across the U.S., 40% of the top-selling baby formula products were out of stock as of the week ending April 24, a new analysis from Datasembly, which tracked baby formula stock at more than 11,000 stores, shows. National out-of-stock levels jumped nine percentage points, from 31% to 40% between April 3 and April 24. That's up sharply from 11% in November.

"This is a shocking number that you don't see for other categories," Ben Reich, CEO of Datasembly told CBS MoneyWatch.