File:Diminishing Returns Chart.png

Formulas
First derivative of Quick Respawn % change $$= (99 / 100 - 81 * A / 5000) / 45$$

First derivative of Bomb Range Up, Quick Super Jump, Run Speed Up, Special Saver % change $$= (99 / 100 - 81 * A / 5000) / 60$$

First derivative of Ink Recovery Up, Ink Saver (Main) % change = $$(99 / 100 - 81 * A / 5000) / (200 / 3)$$

First derivative of Special Duration Up % change $$= (99 / 100 - 81 * A / 5000) / 75$$

First derivative of Damage Up, Defense Up, Special Charge Up % change $$= (99 / 100 - 81 * A / 5000) / 100$$

First derivative of Swim Speed Up % change $$= (99 / 100 - 81 * A / 5000) / 120$$