Mongols - Improved Superior Mobility gives +80% move speed, instead of "+70%" like the description says

For Mongols, the new “Improved Superior Mobility” from the Ovoo gives “+70%” faster move speed for packed buildings. However, it actually gives +80% move speed.

Move Speed of Packed Buildings:

  • Base: 0.75 tiles/sec
  • Upgrade: Superior Mobility (+50%)
    • Expected: 0.75 * 150% = 1.125 tiles/sec
    • Actual: 1.125 tiles/sec
  • Upgrade: Improved Superior Mobility (+70%)
    • Expected: 0.75 * 170% = 1.275 tiles/sec
    • Actual: 1.35 tiles/sec <<< Actually +80% = 180% = 150% * 120%

It seems the “+20%” from the improved upgrade is multiplicative, instead of additive: 150% * 120% = 180% = +80% move speed.

Build: 11.1.1201