Unit speed calculations

Here is a summary of how unit speed is calculated.

speed = base_speed * (1 + infra_bonus / 100) *

(1 + terrain_modifier / 100) *

(1 + enemy_territory_penalty / 100) *

(1 + HP_penalty / 100) *

forced_march

The infrastructure bonus is either 0, 67, 133, or 200. I'm not sure if damaged infrastructure is slower but I'm looking at a damaged level 1 infrastructure with 3 out of 20 HP and it still says "Land unit speed: +67%"

The terrain modifier can be plus or minus or zero. The enemy territory penalty is either zero or -50.

The HP penalty is zero if the percentage of a units HP is >= 50%. Otherwise it is negative as HP / max_HP * 100 - 50. For example 2.4 out of 27 HP would give a penalty of 2.4 / 27 * 100 - 50 = -41.1%. resulting in a speed multiplier of 1 - 41.1 / 100 = 0.589. At zero HP the speed would be one half.

HP penalties are applied to each unit type/level in a stack separately based on their individual HP percentages (not the HP percentage of the stack as a whole) and the stack moves at the speed of the slowest resulting speed.

Forced march is either 1 (off) or 1.5 (on).