The AddDate function takes three arguments in logical order of years, months, and days.
Example: Randomized Tweets from the Last 2 Years
Let's assume you have a file at data/tweets.toml that contains a list of Tweets to display on your site's homepage. The file is filled with [[tweet]] blocks; e.g.---
[[tweet]]
name = "Steve Francia"
twitter_handle = "@spf13"
quote = "I'm creator of Hugo. #metadocreference"
link = "https://twitter.com/spf13"
date = "2017-01-07T00:00:00Z"
Let's assume you want to grab Tweets from the last two years and present them in a random order. In conjunction with the where and now functions, you can limit our range to the last two years via now.AddDate -2 0 0, which represents a point in time 2 years, 0 days, and 0 hours before the time of your last site build.
{{< code file="partials/templates/random-tweets.html" download="tweets.html" >}}
{{ range where $.Site.Data.tweets.tweet "date" "ge" (now.AddDate -2 0 0) | shuffle }}