What does the dots mean on some case knives?

The dots on Case knives can be used to determine the date of manufacture. Starting in 1970, Case added 10 dots to the stamped
imprint and removed one dot each year. This continued with a redesigned
stamp and dots in 1980. They removed the dots in 1990, but due to collector demand , Case brought them back in 1993 until 2000. From 2000
on they now have x's and dots.