Difference between Blue Circuit calculator and Chart

[mitchk1303]

Does anyone know why there is a difference between the blue seas wire gauge calculator and the chart? When sizing my battery cable (200 max amp draw) 4ft total cable length) the calculator says I should use 2AWG for 3 percent drop. But the chart says I should be using 2/0 cable. When I look at the fuse chart it says I should use a 200A T-series fuse for my cable, however 200A is my max draw and the calculator says that 2AWG can handle 200A so I would expect the fuse size to be more like 225 or 250.

Any reason these values are different?