diff --git a/test/unit/test_hist_config.py b/test/unit/test_hist_config.py
index 666ba23b..fa5435f6 100644
--- a/test/unit/test_hist_config.py
+++ b/test/unit/test_hist_config.py
@@ -210,7 +210,7 @@ def test_bad_user_nl_cam(self):
 
         exception_split = str(err.exception).split('\n')
         errmsg_expected = ["No identifiers found, at",
-                           "period must be one of nsteps, nstep, nseconds, nsecond, nminutes, nminute, nhours, nhour, ndays, nday, nmonths, nmonth, nyears, nyear, steps, seconds, minutes, hours, days, months, years, at",
+                           "period (\"1+nmonths\") must be one of nsteps, nstep, nseconds, nsecond, nminutes, nminute, nhours, nhour, ndays, nday, nmonths, nmonth, nyears, nyear, steps, seconds, minutes, hours, days, months, years, at",
                            "precision must be one of REAL32, REAL64, at",
                            "Found invalid identifiers",
                            "T&U&V, at",