https://heat-map.freecodecamp.rocks
The example data structure is:
“baseTemperature”: 8.66,
{
“year”: 1753,
“month”: 1, // January
“variance”: -1.366
},
I found the visualization result doesn’t match the calculation. The 1753 data point should display (8.66 - 1.366) = 7.294, but it shows 6.6. This discrepancy occurs because D3.js uses 0-based month indexing (0-11) for axis formatting. To fix this, we need to adjust the month value by subtracting 1 when binding data coordinates, while updating the tooltip to display the original month number (1-12).
it’s right? if right please fix it 
no wrong please reply 
I just hovered over that year and it has 7.3 so there rounding off 7.294, I don’t see 6.6 anywhere.
sorry, it shows 6.4℃. i think maybe the first month (month = 1) is December not January . right? 