Numbers can be tricky with text to speech systems. Say you wrote 1979. Did you mean the year nineteen seventy-nine, or did you mean the number one thousand nine hundred seventy-nine?

The text to speech system has no way of knowing exactly which way you would like it to pronounce the number. It will guess to the best of its abilities from the context, but it can get it wrong from time to time.

Therefore, for numbers, if you are facing an issue, the best practice is to space out the numbers as you want it to sound.

Phone numbers

958-2910-2992 => 9 5 8, 2 9 1 0, 2 9 9 2 (adding commas will create natural pauses as if someone is reading the number out)

Date

10/29/1992 => October 29, 19 92

1990s => 19 nineties

80s => eighties

Time

9:10 AM => 9 10 AM

Decimals

69.39 => 69 point 3 9