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Checking on pivot point levels

I have just checked my data and I have the following numbers for last weeks September Eurostoxx contract.

Open 2649
High 2773
Low 2569
Close 2751

Using these numbers with the pivot point calculator I am miles away from the numbers published for this weeks weekly pivots.

Does anyone have an explanation? In both cases I am looking at the figures for the 'classic' pivots.
Around this time of the quarter the biggest mistake that would lead to this difference is using the wrong contract. e.g. looking at September contract on the daily notes but calculating pivots for December contract. Also, the weekly OHLC figures that you have might come from a mix of contracts, is that possible?