So many loves start with a "hey." A tentative "hey." A hopeful "hey." And more often than ever that "hey" is not spoken, but sent through a text message.

That first "hey," if all goes well, is returned; from there, the "hey" becomes a plan to get together. Which becomes another plan to get together. And then more plans, and then more plans, until making plans becomes redundant.

In October of 2009, Alice Zhao's boyfriend gave her a gift to celebrate the one-year anniversary of their first date: a Word document containing all of the text messages they'd exchanged during the previous year. He called his present, awesomely, #thegiftofdata. This October, to commemorate their sixth year together, Zhao took that Word doc and expanded it. She took the texts from their first year together and then compared them to another set of data she'd gathered: texts from their sixth year—a year that saw the two transitioning from engaged to newlywed.

What Zhao found was, if not scientifically rigorous, then romantically revealing.

First, she compared some of the most commonly-used terms in the couple's text messages—"love," "ok," "dinner," and, yes, "hey"—looking at their distribution in year one versus year six.

As Zhao notes, the relative distribution of those terms loosely tracks the comfort that set in as the pair shifted their interactions from on-phone to in-person. "Our conversations changed from 'hey, what’s up?' to 'ok, sounds good,'" she writes in a blog post explaining the project. "We stopped saying each other’s names in our text messages. We don’t say in 'love' as much anymore."

Names, too, became extra-superfluous as the pair settled into coupledom.

What didn't much change in frequency were references to two things that are constant no matter your relationship status: "home" and "dinner." For the couple, those terms simply appeared in different contexts in year six than they had in year one. "Home" became a reference to the couple's shared home. "Dinner" became less a matter of if and more one of when and how.

What also changed were the times of day that were peak messaging times for the couple. When they were first dating, the bulk of the messages were sent in the late afternoon and evening, and also between midnight and 3 a.m. During the period of their engagement, though, things were largely reversed: The bulk of their messages were sent during the day and, to a lesser extent, into the evening. After their wedding, the texts were even more limited to the daytime hours: They texted each while at work, but almost never at other times.

Or, as Zhao decodes it:

Overall, the changes as Zhao sums it up:

As a new couple, since we were apart the majority of the time, we had to check in with the other person every now and then, especially during the evening and late at night when we had no idea who they were with! It was also to tell the other person that we were out late doing something cool without them… and wishing they were there, of course.

As a committed couple, the only time of the day that we aren’t together is during the workday, so that’s when we text. We know exactly where the other person is each evening and if we’re doing something cool, it’s likely that we’re in it together and telling each other about it face to face.

As for one of the biggest surprises in the data, the decline of the word "love" as the relationship progresses? "Our text messages became more predictable, but only because all of the unpredictable things were said in person," Zhao explains. "We no longer have to text 'I love you' from a distance in the middle of the night. I can now roll over, snuggle with my husband and whisper it into his ear."