diff --git a/src/protocol/prf_sharding/mod.rs b/src/protocol/prf_sharding/mod.rs
index 946887b35..07404509e 100644
--- a/src/protocol/prf_sharding/mod.rs
+++ b/src/protocol/prf_sharding/mod.rs
@@ -363,32 +363,6 @@ where
     })
 }
 
-// fn chunk_rows_by_user<BK, TV, TS>(
-//     input_rows: Vec<PrfShardedIpaInputRow<BK, TV, TS>>,
-// ) -> Vec<Vec<PrfShardedIpaInputRow<BK, TV, TS>>>
-// where
-//     BK: GaloisField,
-//     TV: GaloisField,
-//     TS: GaloisField,
-// {
-//     let mut rows_for_user: Vec<PrfShardedIpaInputRow<BK, TV, TS>> = vec![];
-
-//     let mut rows_chunked_by_user = vec![];
-//     for row in input_rows {
-//         if rows_for_user.is_empty() || row.prf_of_match_key == rows_for_user[0].prf_of_match_key {
-//             rows_for_user.push(row);
-//         } else {
-//             rows_chunked_by_user.push(rows_for_user);
-//             rows_for_user = vec![row];
-//         }
-//     }
-//     if !rows_for_user.is_empty() {
-//         rows_chunked_by_user.push(rows_for_user);
-//     }
-
-//     rows_chunked_by_user
-// }
-
 /// Sub-protocol of the PRF-sharded IPA Protocol
 ///
 /// After the computation of the per-user PRF, addition of dummy records and shuffling,
@@ -485,13 +459,8 @@ where
         0..BK::BITS + TV::BITS,
     );
 
-    // transform value bits to large field
-    // let large_field_values = converted_values
-    //     .map(|val| BitDecomposed::to_additive_sharing_in_large_field_consuming(val.unwrap()));
-
     // move each value to the correct bucket
     let row_contributions_stream = converted_bks_and_tvs
-        // .zip(large_field_values)
         .zip(futures::stream::repeat(
             prime_field_ctx.narrow(&Step::MoveValueToCorrectBreakdown)
                 .set_total_records(num_outputs),
diff --git a/src/query/runner/oprf_ipa.rs b/src/query/runner/oprf_ipa.rs
index e77a0300e..def96d26e 100644
--- a/src/query/runner/oprf_ipa.rs
+++ b/src/query/runner/oprf_ipa.rs
@@ -71,6 +71,18 @@ where
             panic!("Encrypted match key handling is not handled for OPRF flow as yet");
         };
 
+        let mut histogram = vec![];
+        let mut last_prf = input[0].mk_oprf + 1;
+        let mut cur_count = 0;
+        for row in input {
+            if row.mk_oprf != last_prf {
+                cur_count = 0;
+            } else {
+                cur_count += 1;
+            }
+            histogram[cur_count] += 1;
+        }
+
         // TODO: Compute OPRFs and shuffle and add dummies and stuff (Daniel's code will be called here)
         let sharded_input = input
             .into_iter()
@@ -110,6 +122,7 @@ where
             sharded_input,
             user_cap.ilog2().try_into().unwrap(),
             config.attribution_window_seconds,
+            &histogram,
         )
         .await
     }