From
n x r = (100 - r) x (100 - n) + (-100^2 + 100n + 100r)
example
95 x 96 = ((95-(100-96)=91)x100 = 9100) + ((100-95)x(100-96) = 20) = 9120
92 x 94 = ((92-(100-94)=86)x100 = 8600) + ((100-92)x(100-94) = 48) = 8648
106 x 107 = ((106-(100-107)=113)x100 = 11300) + ((100-106)x(100-107) = 42) = 11342
91 x 104 = ((91-(100-104)=95)x100 = 9500) + ((100-91)x(100-104) = -36) = 9464