And the amount we receive depends also on the distance, since Earth's orbit is 0.017 eccentric. And so on.
Ice ages have been related to periodic changes in Earth's inclination and with the orientation of its inclination versus the seasons - over times where continents moved little. This does not explain the changes over the past millennium, but attempts to explain them by a varying Solar output are debatable and debated. In favour of less Sun power then are the fewer Sunspots observed at that time. But the tiny value of the power drop speaks against that explanation, and other causes, for instance changes at the Gulf Stream, are considered.
Anyway, changes like 10% aren't realistic in modern history, nor can the Solar output explain the present global warming.