We use the Present Perfect when the time period is continuing.
Again there is a connection between the past and the present.
Example
I have played tennis today.
Today started at midnight and is continuing.
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12am |
1pm |
Future |
So even though the action has finished the time period is continuing, so there is a connection between the past and the present. We therefore use the present perfect.
Example
I have been on holiday this year.
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1st January
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16 May |
Future |
This year started on 1st January, today is 16th May for example, so it started in the past, is continuing and so we use the present perfect.