84% is misleading. The true percentage is:
Attack 223 + 13 = 236 = 99.2 %
Defense 176 + 11 = 187 = 97.9 %
Stamina 156 + 14 = 170 = 99.4 %
If you had 0% IV then you still perform 93.6 %, 92.1 % and 91.2 % respectively. Since defense and stamina effectively multiply, 0% IV would make you last 16% shorter than a 100% IV. You are missing 2.7 %.