diff --git a/regtest/basic/rt71/plumed.dat b/regtest/basic/rt71/plumed.dat
index 84207505a66767b7ed21ed1762bce5adeeaaaa8e..c4ecf3c5b0ad12fd78f97f8ab658f3dc0d859bfa 100644
--- a/regtest/basic/rt71/plumed.dat
+++ b/regtest/basic/rt71/plumed.dat
@@ -5,7 +5,7 @@ d: DISTANCE ATOMS=at,2 COMPONENTS NOPBC
 
 # alternative calculation:
 p: POSITION ATOM=2 NOPBC
-one: CONSTANT VALUES=1.0
+one: CONSTANT VALUE=1.0
 dx: COMBINE ARG=p.x,one COEFFICIENTS=1,-1 PERIODIC=NO
 dy: COMBINE ARG=p.y,one COEFFICIENTS=1,-2 PERIODIC=NO
 dz: COMBINE ARG=p.z,one COEFFICIENTS=1,-3 PERIODIC=NO
diff --git a/regtest/basic/rt71b/plumed.dat b/regtest/basic/rt71b/plumed.dat
index 09ac6ee9b69e0dac54d266091eaefecad11762f8..265eac843d90995bbc95df59368a45edaecb68a6 100644
--- a/regtest/basic/rt71b/plumed.dat
+++ b/regtest/basic/rt71b/plumed.dat
@@ -5,7 +5,7 @@ d: DISTANCE ATOMS=at,2 SCALED_COMPONENTS NOPBC
 
 # alternative calculation:
 p: POSITION ATOM=2 NOPBC SCALED_COMPONENTS
-one: CONSTANT VALUES=1.0
+one: CONSTANT VALUE=1.0
 da: COMBINE ARG=p.a,one COEFFICIENTS=1,-0.1 PERIODIC=NO
 db: COMBINE ARG=p.b,one COEFFICIENTS=1,-0.2 PERIODIC=NO
 dc: COMBINE ARG=p.c,one COEFFICIENTS=1,-0.3 PERIODIC=NO