diff --git a/exec/Chainweb/Coins.hs b/exec/Chainweb/Coins.hs
index 1da14b8a..babcfe83 100644
--- a/exec/Chainweb/Coins.hs
+++ b/exec/Chainweb/Coins.hs
@@ -54,7 +54,8 @@ newtype CsvTime = CsvTime { _csvTime :: UTCTime }
 instance CSV.FromField CsvTime where
     parseField f = either fail pure ev
       where
-        ev = fmap CsvTime . parseTimeM True defaultTimeLocale "%FT%TZ" =<<
+        ev = maybe (Left $ "Error parsing CsvTime " <> show f) (Right . CsvTime) .
+          parseTimeM True defaultTimeLocale "%FT%TZ" =<<
           bimap show T.unpack (decodeUtf8' f)
 
 newtype MinerRewards = MinerRewards