diff --git a/DESCRIPTION b/DESCRIPTION
index 79c605fb7f71dabb4fe27ad876c17f691c3acc07..0b28c6857efc6a83458831993b45c1209ac9e66e 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: airGR
 Type: Package
 Title: Suite of GR Hydrological Models for Precipitation-Runoff Modelling
-Version: 1.6.1.4
+Version: 1.6.1.5
 Date: 2020-04-05
 Authors@R: c(
   person("Laurent", "Coron", role = c("aut", "trl"), comment = c(ORCID = "0000-0002-1503-6204")),
diff --git a/NEWS.md b/NEWS.md
index 51dcad03ac2e96ee601a641da64abb281ea84d0d..26f70024448c0d5da3baa56ad7fed63996b25b44 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -2,7 +2,7 @@
 
 
 
-### 1.6.1.4 Release Notes (2020-04-05)
+### 1.6.1.5 Release Notes (2020-04-05)
 
 #### New features
 
diff --git a/R/RunModel.R b/R/RunModel.R
index e8f7cf1f97e417fb600b82186f74894795a54378..dc135b289364c8e0fb32e4ca18adc71f350b5e1f 100644
--- a/R/RunModel.R
+++ b/R/RunModel.R
@@ -12,7 +12,7 @@ RunModel <- function (InputsModel, RunOptions, Param, FUN_MOD) {
     }
     AreaTot <- sum(InputsModel$BasinAreas)
     OutputsModelDown$Qsim <- OutputsModelDown$QsimDown * InputsModel$BasinAreas[length(InputsModel$BasinAreas)] / AreaTot +
-      1000 / Param[-length(Param)] / TimeStep * 
+      1000 / Param[length(Param)] / TimeStep * 
       InputsModel$QobsUpstr %*% (InputsModel$LengthHydro[1, ] * InputsModel$BasinAreas[1:length(InputsModel$LengthHydro)])
   } else {
     OutputsModelDown <- FUN_MOD(InputsModel = InputsModel, RunOptions = RunOptions, Param = Param)