diff --git a/Trigger/TrigCost/TrigCostAnalysis/src/CostData.cxx b/Trigger/TrigCost/TrigCostAnalysis/src/CostData.cxx
index d3cd438bb1365414a4971084dae5c46865820bc3..cc43b20711d7e442becb0d9d392cb595c446f403 100644
--- a/Trigger/TrigCost/TrigCostAnalysis/src/CostData.cxx
+++ b/Trigger/TrigCost/TrigCostAnalysis/src/CostData.cxx
@@ -88,6 +88,10 @@ const std::map<std::string, std::vector<uint32_t>>& CostData::rosToRobMap() cons
   return *m_rosToRob;
 }
 
+const std::map<size_t, std::vector<size_t>>& CostData::algToRequestMap() const {
+  return m_algToRos;
+}
+
 float CostData::algTotalTimeMilliSec() const {
   return m_algTotalTime * 1e-3; // microseconds to milliseconds
 }
diff --git a/Trigger/TrigCost/TrigCostAnalysis/src/CostData.h b/Trigger/TrigCost/TrigCostAnalysis/src/CostData.h
index ef33493962ee0f3d0dc261e644944b8bd65912ec..dd54a8fbc8f44b4fc1e0f7f6985ff59f47ed2b7e 100644
--- a/Trigger/TrigCost/TrigCostAnalysis/src/CostData.h
+++ b/Trigger/TrigCost/TrigCostAnalysis/src/CostData.h
@@ -66,6 +66,11 @@ class CostData {
      */
     void setRosToRobMap(const std::map<std::string, std::vector<uint32_t>>& rosToRobMap);
 
+    /**
+     * @brief Getter of map between algorithm (index in costCollection) and ROS requests (indicies in rosCollection)
+     */
+    const std::map<size_t, std::vector<size_t>>& algToRequestMap() const;
+
     /**
      * @brief Setter of effective P1 walltime represented by the current event.
      */
diff --git a/Trigger/TrigCost/TrigCostAnalysis/src/counters/CounterAlgorithm.cxx b/Trigger/TrigCost/TrigCostAnalysis/src/counters/CounterAlgorithm.cxx
index 9d942f27d495cee52f5ef6f618d0c6a4b057ff8b..23daafff343c86f2c6f1077fb814e7ef517fac70 100644
--- a/Trigger/TrigCost/TrigCostAnalysis/src/counters/CounterAlgorithm.cxx
+++ b/Trigger/TrigCost/TrigCostAnalysis/src/counters/CounterAlgorithm.cxx
@@ -3,6 +3,7 @@
 */
 
 #include "xAODTrigger/TrigCompositeContainer.h"
+#include "TrigDataAccessMonitoring/ROBDataMonitor.h"
 
 #include "CounterAlgorithm.h"
 
@@ -16,6 +17,11 @@ CounterAlgorithm::CounterAlgorithm(const std::string& name, const MonitorBase* p
   regHistogram("AlgCalls_perEvent", "Calls/Event;Calls;Events", VariableType::kPerEvent, kLinear, -0.5, 49.5);
   regHistogram("InEventView_perCall", "In Event View;Yes or No;Calls", VariableType::kPerCall, kLinear, -0.5, 1.5, 2);
   regHistogram("RoIID_perCall", "RoI ID;RoI ID;Calls", VariableType::kPerCall, kLinear, -1.5, 20.5, 22);
+  regHistogram("Request_perEvent", "Number of requests/Event;Number of requests;Events", VariableType::kPerEvent, LogType::kLinear, -0.5, 10.5, 11);
+  regHistogram("NetworkRequest_perEvent", "Number of network requests/Event;Number of requests;Events", VariableType::kPerEvent, LogType::kLinear, -0.5, 10.5, 11);
+  regHistogram("CachedROBSize_perEvent", "Total ROB Size/Event;ROB size;Events", VariableType::kPerEvent, LogType::kLinear, 0, 1024, 50);
+  regHistogram("NetworkROBSize_perEvent", "Total ROB Size/Event;ROB size;Events", VariableType::kPerEvent, LogType::kLinear, 0, 1024, 50);
+  regHistogram("RequestTime_perEvent", "ROB Elapsed Time/Event;Elapsed Time [ms];Events", VariableType::kPerEvent);
 }
 
 
@@ -45,5 +51,36 @@ StatusCode CounterAlgorithm::newEvent(const CostData& data, size_t index, const
 
   ATH_CHECK( fill("RoIID_perCall", alg->getDetail<int32_t>("roi"), weight) );
 
+  // Monitor data requests per algorithm
+  if (data.algToRequestMap().count(index)) {
+    for (size_t requestIdx : data.algToRequestMap().at(index)) {
+      const xAOD::TrigComposite* request = data.rosCollection().at(requestIdx);
+      const std::vector<unsigned> robs_history = request->getDetail<std::vector<unsigned>>("robs_history");
+      const std::vector<uint32_t> robs_size = request->getDetail<std::vector<uint32_t>>("robs_size");
+
+      bool networkRequestIncremented = false;
+      for (size_t i = 0; i < robs_size.size(); ++i) {
+        // ROB request was fetched over the network
+        if (robs_history[i] == robmonitor::RETRIEVED) {
+          ATH_CHECK( fill("NetworkROBSize_perEvent", robs_size[i], weight) );
+          networkRequestIncremented = true;
+        }
+        // ROB request was cached
+        else if (robs_history[i] == robmonitor::HLT_CACHED || robs_history[i] == robmonitor::DCM_CACHED) {
+          ATH_CHECK( fill("CachedROBSize_perEvent", robs_size[i], weight) );
+        }
+      }
+
+      ATH_CHECK( increment("Request_perEvent", weight) );
+
+      if (networkRequestIncremented) {
+        ATH_CHECK( increment("NetworkRequest_perEvent", weight) );
+      }
+
+      const float rosTime = timeToMilliSec(request->getDetail<uint64_t>("start"), request->getDetail<uint64_t>("stop"));
+      ATH_CHECK( fill("Time_perEvent", rosTime, weight) );
+    }
+  }
+
   return StatusCode::SUCCESS;
 }