Earned Value Management gives project managers a single coherent view of whether a project is on time and within budget — two questions that standard tracking usually answers separately. The three core inputs (what you planned to spend, what you've actually spent, and the budgeted cost of work done) feed into a set of ratios that expose both cost efficiency and schedule performance. A CPI below 1 means you're getting less value per pound than planned; an SPI below 1 means progress is slower than the schedule assumed.