rvest - scraping data for federal holidays

I am new to scrapping data off the web and seem to be having some issues. I am trying to scrape data from this link for 2016 and 2017:

https://www.officeholidays.com/countries/usa/2017.php

I have tried a million different ways. Here my last attempt where I try to copy the xpath:

library(rvest)

url <- "https://www.officeholidays.com/countries/usa/2017.php"
holiday <- url %>%
  read_html() %>%
  html_nodes(xpath = "//*[@id="wrapper"]/div[3]/div[2]/table[1]") %>%
  html_table()