Convert the audio playback speed to percentage.
Normal playback speed is 1, meaning the audio is played at the normal speed.
yarn add speed-to-percentage
import speedToPercentage from 'speed-to-percentage'
const half = speedToPercentage(0.5) // returns the string -50
const moreDigits = speedToPercentage(0.5, 2) // returns the string -50.00