diff --git a/Hledger/Reports/ReportTypes.hs b/Hledger/Reports/ReportTypes.hs
--- a/Hledger/Reports/ReportTypes.hs
+++ b/Hledger/Reports/ReportTypes.hs
@@ -89,7 +89,7 @@
   } deriving (Show, Functor, Generic, ToJSON)
 
 instance Bifunctor PeriodicReport where
-  bimap f g pr = pr{prRows = map (bimap f g) $ prRows pr, prTotals = fmap g $ prTotals pr}
+  bimap f g pr = pr{prRows = map (bimap f g) $ prRows pr, prTotals = g <$> prTotals pr}
 
 data PeriodicReportRow a b =
   PeriodicReportRow
diff --git a/hledger-lib.cabal b/hledger-lib.cabal
--- a/hledger-lib.cabal
+++ b/hledger-lib.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           hledger-lib
-version:        1.27
+version:        1.27.1
 synopsis:       A reusable library providing the core functionality of hledger
 description:    A reusable library containing hledger's core functionality.
                 This is used by most hledger* packages so that they support the same