If yes, then this write-up may shed some light on that. But this knowledge has been lost and tainted over the centuries. Now a days there is concerted effort to restore and decipher this knowledge- by some Indian scholars around the world. And that is helping us in understanding our glorious past. It will go a long way in restoring our pride and it will bring to us a sense of gladness and respect about our past and heritage.
Lets get back to the subject.
Sadly, to prove that we compare it to the modern system. We will not divert too much by comparing them both. But to give an example, Indians in ancient times had calculated the time period for a cycle of creation of our universe till its destruction as 8 .64 billion years. Interesting , because that is what the modern scientists claim too- based on their scientific calculations. Ancient Indians had defined larger time cycles too.