optimum property
Indicates the optimal numeric value. It must be within the range (as defined by the min attribute and max attribute). When used with the low attribute and high attribute, it gives an indication where along the range is considered preferable. For example, if it is between the min attribute and the low attribute, then the lower range is considered preferred. The browser may color the meter's bar differently depending on whether the value is less than or equal to the optimum value.
Implementation
final double? optimum;