Using COUNTIFS does not return correct value when looking at Hours:Minutes:Seconds

So, here is the issue.....

I have a range of data that looks at the difference in time from one cycle to the next. This range can extend to 5000 cells. the format comes out as below

00:00:40
00:00:38
00:00:39
00:00:35
00:00:46
00:00:42
etc.....

What i need to calculate is the number of times an occurance falls into a certain time frame ( so how many occurances are between 00:00:40 and 00:00:45 for example)

The formula i am using is below where the criteria changes depending on what range i am looking for.

=COUNTIFS(E3:E4997,">=00:00:00",E3:E4997,"<=00:00:31")

When i am calculating the lowest range (00:00:00 to 00:00:30) it does not calulate the correct amount and i have to change the <=00:00:30 to <=00:00:31 for it to be correct. Even then, the calulation may be out by a few.

I have attached an example of the sheet and added some comments. Any help would be appriciated here as its doing my head in!!!!!

You need to ommit second <= because then it will be used twice.

In case exactly 00:00:31 both formulae will calculate it:

Formula:

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You should use:

Formula:

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Same for all other formula.
(Replace ; with ,)

Just to note: both (mine and ConneXionLost) approaches are OK.
It's just important not to calculate same values twice.