Google analytics: total of internal and external traffic is less then all traffic?

On Google Analytics, I've created 3 profiles:

• All traffic (no filter)
• Internal (inclusive filter by IP range)
• External (exclusive filter by the same 开发者_JS百科IP range as in Internal)

I let all profiles run for a week to accumulate the data. My logic is the sum of the Internal and External should be the same as All traffic.

However, the totals don't match and All traffic reports higher figures than the combined total of the other two profiles.

For example, page views are reported as follows: Internal (23), External (158) and All (186), which is greater than the sum (23+158 = 181)!

If anyone encountered similar issue, please advise on the solution. Thank you!

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I have two separate websites set up in a similar manner and the results are this:

Site 1:

External - 19,842

Internal - 1,327

Raw - 21,162

Difference (-7)

Site 2:

External - 2,799

Internal - 340

Raw - 3,078

Difference (+61)

That's close enough.

Your numbers are so close that I doubt anything is wrong in the set up.

Google Analytics is not an exact (100%) accurate reporting system. None of them are. Anomalies happen and some sampling on the data for reporting may be done which slightly skew the numbers.