diff --git a/opm/input/eclipse/Schedule/Group/Group.hpp b/opm/input/eclipse/Schedule/Group/Group.hpp
index e394cd0155d..4b8b72d7c05 100644
--- a/opm/input/eclipse/Schedule/Group/Group.hpp
+++ b/opm/input/eclipse/Schedule/Group/Group.hpp
@@ -119,8 +119,7 @@ class Group {
         VOID = 2,
         NETV = 3,
         RESV = 4,
-        POTN = 5,
-        NO_GUIDE_RATE = 6
+        NO_GUIDE_RATE = 5
     };
     static GuideRateInjTarget GuideRateInjTargetFromString( const std::string& stringValue );
     static GuideRateInjTarget GuideRateInjTargetFromInt(int ecl_id);
diff --git a/opm/input/eclipse/Schedule/Group/GuideRate.cpp b/opm/input/eclipse/Schedule/Group/GuideRate.cpp
index e05f8e7ea55..75ca53ddb4b 100644
--- a/opm/input/eclipse/Schedule/Group/GuideRate.cpp
+++ b/opm/input/eclipse/Schedule/Group/GuideRate.cpp
@@ -283,22 +283,22 @@ void Opm::GuideRate::group_compute(const std::string& wgname,
     }
 }
 
-void Opm::GuideRate::compute(const std::string& wgname,
-                             const Phase&       phase,
-                             const std::size_t  report_step,
-                             const double       guide_rate)
+void Opm::GuideRate::compute(const std::string&          wgname,
+                             const Phase&                phase,
+                             const std::size_t           report_step,
+                             const std::optional<double> guide_rate)
 {
     const auto& config = this->schedule[report_step].guide_rate();
     if (!config.has_injection_group(phase, wgname))
         return;
 
-    if (guide_rate > 0) {
-        this->injection_group_values[std::make_pair(phase, wgname)] = guide_rate;
+    if (guide_rate) {
+        this->injection_group_values[std::make_pair(phase, wgname)] = *guide_rate;
         return;
     }
 
     const auto& group = config.injection_group(phase, wgname);
-    if (group.target == Group::GuideRateInjTarget::POTN) {
+    if (group.target == Group::GuideRateInjTarget::NO_GUIDE_RATE) {
         return;
     }
     this->injection_group_values[std::make_pair(phase, wgname)] = group.guide_rate;
diff --git a/opm/input/eclipse/Schedule/Group/GuideRate.hpp b/opm/input/eclipse/Schedule/Group/GuideRate.hpp
index 110b353f8d4..79ab0165098 100644
--- a/opm/input/eclipse/Schedule/Group/GuideRate.hpp
+++ b/opm/input/eclipse/Schedule/Group/GuideRate.hpp
@@ -122,10 +122,10 @@ class GuideRate
                  const double       gas_pot,
                  const double       wat_pot);
 
-    void compute(const std::string& wgname,
-                 const Phase&       phase,
-                 const std::size_t  report_step,
-                 const double       guide_rate);
+    void compute(const std::string&          wgname,
+                 const Phase&                phase,
+                 const std::size_t           report_step,
+                 const std::optional<double> guide_rate);
 
     bool has(const std::string& name) const;
     bool hasPotentials(const std::string& name) const;
diff --git a/tests/parser/GroupTests.cpp b/tests/parser/GroupTests.cpp
index 0f5fdefb43d..250e1cef958 100644
--- a/tests/parser/GroupTests.cpp
+++ b/tests/parser/GroupTests.cpp
@@ -604,10 +604,10 @@ GCONINJE
         GuideRate gr = GuideRate(schedule);
         const auto& g1 = schedule.getGroup("G1", 1);
         const auto& g2 = schedule.getGroup("G2", 1);
-        gr.compute(g1.name(), Phase::WATER, 1, 0.0);
-        gr.compute(g1.name(), Phase::GAS, 1, 0.0);
-        gr.compute(g2.name(), Phase::WATER, 1, 0.0);
-        gr.compute(g2.name(), Phase::GAS, 1, 0.0);
+        gr.compute(g1.name(), Phase::WATER, 1, std::nullopt);
+        gr.compute(g1.name(), Phase::GAS, 1, std::nullopt);
+        gr.compute(g2.name(), Phase::WATER, 1, std::nullopt);
+        gr.compute(g2.name(), Phase::GAS, 1, std::nullopt);
 
         BOOST_CHECK( gr.has(g1.name(), Phase::WATER));
         BOOST_CHECK( gr.has(g1.name(), Phase::GAS));