Cloudwatch – how to use percentile?

I thought percentile was something that was supported in Cloudwatch, but if i try to add this to my query:

| stats precentile(someValue, 90)

For getting the p90 of someValue, it complains that precentile is not a recognized option..
Does Cloudwatch not support precentile?

>Solution :

I think you are looking for pct:

pct(fieldName: LogFieldValue, percent: number)

A percentile indicates the relative standing of a value in a dataset. For example, pct(@duration, 95) returns the @duration value at which 95 percent of the values of @duration are lower than this value, and 5 percent are higher than this value.

Source: aws docs