Code
%>%
NY.GDP.MKTP.CN.AD left_join(iso2c, by = "iso2c") %>%
group_by(iso2c, iso2c_desc) %>%
rename(value = value) %>%
mutate(value = round(value/(10^9))) %>%
summarise(Nobs = n(),
`Year 1` = first(year),
`GDP 1 (Bn)` = first(value),
`Year 2` = last(year),
`GDP 2 (Bn)` = last(value)) %>%
arrange(-Nobs) %>%
if (is_html_output()) datatable(., filter = 'top', rownames = F) else .} {