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Now there are some important things to note about the data set. In most cases where you have poll trends over time, you have clear apples to apples comparisons. So for instance in the Obama National Approval data set you have various pollsters all using identical or nearly identical wording. With the Health Care Reform polling, however, pollsters are using very different phrasings. Some, for instance, phrase the question in a way that puts all the antis to the right and the left in one big number while others phrase the questions in a way that tends to separate those two groups out. In any case, that adds a significant fuzziness to the trend. But there's simply no way to create a composite otherwise. So bear that in mind with this particular chart.