We are assuming that William (Man in Black) and Logan entered Westworld around 30 years ago. We also know that Westworld was created around 30 years ago. If we assume that William and Logan entered in the first year of the park being open we can deduce that it is 2043 when the Man in Black comes back to the park.
The timelines are as follows:
34 years ago (2009) – Arnold, Ford and Dolores are together before the park opens. We are not 100% certain if Dolores is a host at this point. We do know she was the first host but she might have been Ford’s wife or daughter at this time.
30 year ago (2013) – The park is open and William and Ford first enter the park. We see the old Westworld logo when they arrive via the subway/train. William meets Andrea for the first time and gets to choose which color hat he would like to wear. He chooses white and Logan chooses black.
Today (2043) – The Man in Black is back in Westworld for what he hopes is the last time. He has visited many times in the past. We also know he is a huge financier of the park. He also funded Ford in his initial years of the park being open.
We will likely learn much more about the different timelines in the finale. Expect Jonathan Nolan to do some flashing back and flashing forward during the last 15 to 30 minutes of the finale which will set up Season 2. Who knows what year we will see in season 2.