How to convert a column into a count of occurences (in R)-CodePudding

This question was

This photo shows my current dataframe, containing information on the first year an invasive species was recorded in each country. I am not interested in the taxon data, just the number of taxa, and instead want one row for each country and year, giving a count of the number of taxa that were introduced that year in that country. E.g.

Afghanistan, 1996, 1. Afghanistan, 1974, 1. ... Alaska, 2020, 1. Alaska, 2017, 2. And so on.

I thought about looping through each row, but is there a quicker way to do this?

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library(dplyr)

region <- c("Afghanistan", "Afghanistan", "Afghanistan", "Afghanistan", "Afghanistan", "Afghanistan", "Aland Islands", "Aland Islands", "Aland Islands", "Aland Islands", "Alaska", "Alaska", "Alaska", "Alaska", "Alaska", "Alaska", "Alaska", "Alaska")
firstrecord <- c(1996, 1974, 1972, 1970, 1966, 1964, 2008, 1998, 1934, 1930, 2020, 2017, 2017, 2016, 2016, 2015, 2014, 2014)
df <- data.frame(Region = region, FirstRecord = firstrecord)

df %>% group_by(Region, FirstRecord) %>% summarise(TaxaCount = n())

# A tibble: 15 × 3
# Groups:   Region [3]
   Region        FirstRecord TaxaCount
   <chr>               <dbl>      <int>
 1 Afghanistan          1964          1
 2 Afghanistan          1966          1
 3 Afghanistan          1970          1
 4 Afghanistan          1972          1
 5 Afghanistan          1974          1
 6 Afghanistan          1996          1
 7 Aland Islands        1930          1
 8 Aland Islands        1934          1
 9 Aland Islands        1998          1
10 Aland Islands        2008          1
11 Alaska               2014          2
12 Alaska               2015          1
13 Alaska               2016          2
14 Alaska               2017          2
15 Alaska               2020          1