test_that("constructors create expected classes", {
  ref <- stat_reference(10.4, "unemployment rate", "Spain", "2025", "percent", "Eurostat")
  clm <- stat_claim(10.4, "unemployment rate", "Spain", "2025", "%", "Eurostat")
  expect_s3_class(ref, "stat_reference")
  expect_s3_class(clm, "stat_claim")
  expect_equal(ref$value, 10.4)
  expect_equal(clm$time, "2025")
})