According to a new NPD Group report, US sales of PCs and tablet computers has not witnessed any increase after the late-October launch of Microsoft's newest Windows OS version, Windows 8.

In fact, the NPD report surprisingly revealed that the sales of Windows devices has plunged by 21 percent ever since the October 26 launch of the much-awaited Windows 8 OS, as compared to the sales figures for the same period last year.

In an elaboration of the statistics pertaining to the sales of Windows devices after Windows 8 launch, NPD Group revealed that while notebook sales - which have been rather weak almost all through this year - plunged by 24 percent; while desktop PC sales fell by 9 percent.

The NPD Group report also showed that, during the period from between October 26 and November 17, Windows 8 OS had bagged merely 58 percent of the total unit sales of Windows-based computing devices. In comparison, the Windows 7 version had captured 83 percent of Windows-device unit sales during the first four weeks after its release.

The report also noted that Windows 8 tablet sales had "been almost nonexistent," with unit sales accounting for less than 1 percent of all Windows 8 device sales thus far.

Commenting on the findings, NPD's industry analysis VP Stephen Baker said: "We still have the whole holiday selling season ahead of us, but clearly Windows 8 did not prove to be the impetus for a sales turnaround some had hoped for."