diff --git a/src/opm/output/eclipse/Summary.cpp b/src/opm/output/eclipse/Summary.cpp
index e9ddbf031..d2f7611f6 100644
--- a/src/opm/output/eclipse/Summary.cpp
+++ b/src/opm/output/eclipse/Summary.cpp
@@ -371,6 +371,10 @@ quantity rgip(const fn_args& args) {
     return region_sum( args , "GIP", measure::volume );
 }
 
+quantity rwip(const fn_args& args) {
+    return region_sum( args , "WIP", measure::volume );
+}
+
 quantity roipl(const fn_args& args) {
     return region_sum( args , "OIPL", measure::volume );
 }
@@ -627,6 +631,7 @@ static const std::unordered_map< std::string, ofun > funs = {
     { "ROIPL" , roipl},
     { "ROIPG" , roipg},
     { "RGIP"  , rgip},
+    { "RWIP"  , rwip},
     { "ROIR"  , region_rate< rt::oil, injector > },
     { "RGIR"  , region_rate< rt::gas, injector > },
     { "RWIR"  , region_rate< rt::wat, injector > },
diff --git a/tests/test_Summary.cpp b/tests/test_Summary.cpp
index 98da9261f..b71ffd15c 100644
--- a/tests/test_Summary.cpp
+++ b/tests/test_Summary.cpp
@@ -75,6 +75,7 @@ static data::Solution make_solution( const EclipseGrid& grid ) {
         std::vector<double> roipl(numCells);
         std::vector<double> roipg(numCells);
         std::vector<double> rgip(numCells);
+        std::vector<double> rwip(numCells);
 
         for (size_t k=0; k < grid.getNZ(); k++) {
             for (size_t j=0; j < grid.getNY(); j++) {
@@ -85,6 +86,7 @@ static data::Solution make_solution( const EclipseGrid& grid ) {
                     roipl[g] = roip[g] - 1;
                     roipg[g] = roip[g] + 1;
                     rgip[g] = 2.1*(k + 1);
+                    rwip[g] = 2.2*(k + 1);
                 }
             }
         }
@@ -94,6 +96,7 @@ static data::Solution make_solution( const EclipseGrid& grid ) {
         sol.insert( "OIPL"    , UnitSystem::measure::volume   , roipl, data::TargetType::RESTART_AUXILLARY);
         sol.insert( "OIPG"    , UnitSystem::measure::volume   , roipg, data::TargetType::RESTART_AUXILLARY);
         sol.insert( "GIP"     , UnitSystem::measure::volume   , rgip , data::TargetType::RESTART_AUXILLARY);
+        sol.insert( "WIP"     , UnitSystem::measure::volume   , rwip , data::TargetType::RESTART_AUXILLARY);
     }
     return sol;
 }
@@ -660,6 +663,7 @@ BOOST_AUTO_TEST_CASE(region_vars) {
     for (size_t r=1; r <= 10; r++) {
         std::string rpr_key   = "RPR:"   + std::to_string( r );
         std::string roip_key  = "ROIP:"  + std::to_string( r );
+        std::string rwip_key  = "RWIP:"  + std::to_string( r );
         std::string rgip_key  = "RGIP:"  + std::to_string( r );
         std::string roipl_key = "ROIPL:" + std::to_string( r );
         std::string roipg_key = "ROIPG:" + std::to_string( r );
@@ -671,6 +675,7 @@ BOOST_AUTO_TEST_CASE(region_vars) {
         BOOST_CHECK_CLOSE( area * (2*r - 1) * 1.0  , units.to_si( UnitSystem::measure::volume   , ecl_sum_get_general_var( resp, 1, roipl_key.c_str())) , 1e-5);
         BOOST_CHECK_CLOSE( area * (2*r + 1 ) * 1.0 , units.to_si( UnitSystem::measure::volume   , ecl_sum_get_general_var( resp, 1, roipg_key.c_str())) , 1e-5);
         BOOST_CHECK_CLOSE( area *  2.1*r * 1.0     , units.to_si( UnitSystem::measure::volume   , ecl_sum_get_general_var( resp, 1, rgip_key.c_str())) , 1e-5);
+        BOOST_CHECK_CLOSE( area *  2.2*r * 1.0     , units.to_si( UnitSystem::measure::volume   , ecl_sum_get_general_var( resp, 1, rwip_key.c_str())) , 1e-5);
     }
 }