If you’re not careful, limiting parking capacity could be frustrating for occupants, and not behavior-changing. Consider strategies that go above and beyond the credit requirements:

Encourage carpooling through educational programs and through reward programs for employees who carpool. Choose a strategy that your population would be receptive to, like reduced parking fees or designated parking spots.
Consider subsidizing mass transit passes, and providing information about public transportation and bike routes.
If your project is not located near public transportation, consider setting up a shuttle bus to transport employees to the closest commuter hub, providing an incentive for them not to drive. Survey employees to assess interest in such a service. Doing so could also contribute to SSc3.1.
If you develop a comprehensive transportation management plan that demonstrates a measurable reduction in personal use of cars, you can also earn an Exemplary Performance point through IDc1.