# tick size for US securities

I there a source or way from which I can find out the minimum tick size for US securities at any point in time from 1970 until today? I know that securities above \$1 have \$0.01 tick while those below \$1 have \$0.0001 tick since Jan 29, 2001 but how about before this time?

You probably can't find a definitive resource.

You can however past this together using sources on line.

https://www.finra.org/industry/tick-size-pilot-program

I know that securities above \$1 have \$0.01 tick while those below \$1 have \$0.0001 tick since Jan 29, 2001 but how about before this time?