S&W Model 640 Date Question

[waltherguy]

Hi, today I picked up a very nice S&W Stainless Model 640 .38 Special. The serial number is BKV49XX. Looking for help with the date of manufacture. Anyone with a guide that can let me know would be much appreciated. Thanks,

 

[Lobster Picnic]

Looks like 1991 or '92