PMI Exam PMI-SP Topic 2 Question 84 Discussion

You are the project manager of the HQQ Project. Your project is running late by ten percent of where you should be at this time. Management is concerned and they'd like to know what is your schedule performance index. Considering that the project has a BAC of $567,899, you are thirty percent complete, and you have spent $179,450, what is the SPI for this project?