Daylight Saving Time started as a way to preserve energy and make the most of daylight hours. However in Indiana, it’s been part of a heated debate for nearly 100 years.

Here’s a look at the complicated history with time zones and daylight saving time in Indiana:

1918: Congress approves the Standard Time Act, putting Indiana in the Central Time Zone

1919: Standard Time Act of 1918 repealed

1949: Indiana General Assembly outlaws Daylight Saving Time

1957: New law passed to make Central Time the official time zone of Indiana

1961: Indiana legislature repeals the law made in 1957

1968: Time Life broadcasting leads federal lawsuit to force the observance of DST, and wins

1972: Indiana General Assembly places NW and SW Indiana in the Central Time Zone and the rest of the state on Eastern Time.

2006: The entire state of Indiana becomes the 48th state to observe Daylight Saving Time across the board.

Today: While all of Indiana officially observes Daylight Saving Time, 12 of the 92 counties are on Central Time, with the rest still on Eastern Time.