To the part of native-U.S.-English brain that analyzes logic, you are correct, but the part that speaks U.S. English insists that "savings" feels right and "saving" feels wrong.
The best reason I can come up with is that accumulations of money are "savings" even though you accumulate them by "saving." Perhaps that is because the accumulation (usually!) consists of "dollars," plural.
It feels like a parallel to "potato peelings" or "iron filings" or "snowflakes." All of them are indefinite large masses that we nevertheless recognize as consisting of separate things.
I feel OK saying a company "earns profits" or "earns a profit." I feel OK saying a company "had losses of $234 million" or also "had a loss of $234 million."
Search of gutenberg.org (mostly print books from before 1923) shows 53 hits on "savings of," and virtually all of them concern money: "...the proceeds from the Duchy of Lancaster, which were more than £60,000 a year, the savings of the Prince Consort..." "...to heap the earnings and savings of his life..." "...a purse, containing the savings of months..." "...the savings of her lifetime were burning,--that there was over three thousand dollars in the box..."
It shows 243 for "saving of," but the context is usually not money and not numeric: "...an immense saving of labour and time..." "...These advantages consist indeed wholly in saving of cost of carriage..." "...such arrangement would effect a great saving of water..." "...the great saving of fuel and labour in the management of the engine...." "...the saving of wear and tear..."
I will defy the 57% and say that when the thing being saved is money, and the amount is quoted as an actual known number of dollars or pounds, I prefer the word "savings."