diff --git a/benchmark/string_stats.cpp b/benchmark/string_stats.cpp
new file mode 100644
index 00000000..bc7fa909
--- /dev/null
+++ b/benchmark/string_stats.cpp
@@ -0,0 +1,342 @@
+// Copyright 2021 Peter Dimov.
+// Copyright 2023-2024 Joaquin M Lopez Munoz.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#define _SILENCE_CXX17_OLD_ALLOCATOR_MEMBERS_DEPRECATION_WARNING
+#define _SILENCE_CXX20_CISO646_REMOVED_WARNING
+
+#define BOOST_UNORDERED_ENABLE_STATS
+
+#include <boost/unordered/unordered_flat_map.hpp>
+#include <boost/core/detail/splitmix64.hpp>
+#include <boost/config.hpp>
+#include <unordered_map>
+#include <vector>
+#include <memory>
+#include <cstdint>
+#include <iostream>
+#include <iomanip>
+#include <chrono>
+
+using namespace std::chrono_literals;
+
+static void print_time( std::chrono::steady_clock::time_point & t1, char const* label, std::uint32_t s, std::size_t size )
+{
+    auto t2 = std::chrono::steady_clock::now();
+
+    std::cout << label << ": " << ( t2 - t1 ) / 1ms << " ms (s=" << s << ", size=" << size << ")\n";
+
+    t1 = t2;
+}
+
+constexpr unsigned N = 50'000;
+constexpr int K = 10;
+
+static std::vector<std::string> indices1, indices2;
+
+static std::string make_index( unsigned x )
+{
+    char buffer[ 64 ];
+    std::snprintf( buffer, sizeof(buffer), "pfx_%u_sfx", x );
+
+    return buffer;
+}
+
+static std::string make_random_index( unsigned x )
+{
+    char buffer[ 64 ];
+    std::snprintf( buffer, sizeof(buffer), "pfx_%0*d_%u_sfx", x % 8 + 1, 0, x );
+
+    return buffer;
+}
+
+static void init_indices()
+{
+    indices1.reserve( N*2+1 );
+    indices1.push_back( make_index( 0 ) );
+
+    for( unsigned i = 1; i <= N*2; ++i )
+    {
+        indices1.push_back( make_index( i ) );
+    }
+
+    indices2.reserve( N*2+1 );
+    indices2.push_back( make_index( 0 ) );
+
+    {
+        boost::detail::splitmix64 rng;
+
+        for( unsigned i = 1; i <= N*2; ++i )
+        {
+            indices2.push_back( make_random_index( static_cast<std::uint32_t>( rng() ) ) );
+        }
+    }
+}
+
+template<class Map> BOOST_NOINLINE void test_insert( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.insert( { indices1[ i ], i } );
+    }
+
+    print_time( t1, "Consecutive insert",  0, map.size() );
+
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.insert( { indices2[ i ], i } );
+    }
+
+    print_time( t1, "Random insert",  0, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_lookup( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    std::uint32_t s;
+    
+    s = 0;
+
+    for( int j = 0; j < K; ++j )
+    {
+        for( unsigned i = 1; i <= N * 2; ++i )
+        {
+            auto it = map.find( indices1[ i ] );
+            if( it != map.end() ) s += it->second;
+        }
+    }
+
+    print_time( t1, "Consecutive lookup",  s, map.size() );
+
+    s = 0;
+
+    for( int j = 0; j < K; ++j )
+    {
+        for( unsigned i = 1; i <= N * 2; ++i )
+        {
+            auto it = map.find( indices2[ i ] );
+            if( it != map.end() ) s += it->second;
+        }
+    }
+
+    print_time( t1, "Random lookup",  s, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_iteration( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    auto it = map.begin();
+
+    while( it != map.end() )
+    {
+        if( it->second & 1 )
+        {
+            if constexpr( std::is_void_v< decltype( map.erase( it ) ) > )
+            {
+                map.erase( it++ );
+            }
+            else
+            {
+                it = map.erase( it );
+            }
+        }
+        else
+        {
+            ++it;
+        }
+    }
+
+    print_time( t1, "Iterate and erase odd elements",  0, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_erase( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.erase( indices1[ i ] );
+    }
+
+    print_time( t1, "Consecutive erase",  0, map.size() );
+
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.erase( indices2[ i ] );
+    }
+
+    print_time( t1, "Random erase",  0, map.size() );
+
+    std::cout << std::endl;
+}
+
+//
+
+// All Unordered container use the same struct
+using stats = boost::unordered_flat_map<int, int>::stats; 
+
+struct record
+{
+    std::string label_;
+    long long time_;
+    stats stats_;
+};
+
+static std::vector<record> records;
+
+template<template<class...> class Map> BOOST_NOINLINE void test( char const* label )
+{
+    std::cout << label << ":\n\n";
+
+    Map<std::string, std::uint32_t> map;
+
+    auto t0 = std::chrono::steady_clock::now();
+    auto t1 = t0;
+
+    test_insert( map, t1 );
+
+    record rec = { label, 0 };
+
+    test_lookup( map, t1 );
+    test_iteration( map, t1 );
+    test_lookup( map, t1 );
+    test_erase( map, t1 );
+
+    auto tN = std::chrono::steady_clock::now();
+    std::cout << "Total: " << ( tN - t0 ) / 1ms << " ms\n\n";
+
+    rec.time_ = ( tN - t0 ) / 1ms;
+    rec.stats_ = map.get_stats();
+    records.push_back( rec );
+}
+
+//
+
+template<class K, class V> using boost_unordered_flat_map =
+    boost::unordered_flat_map<K, V, boost::hash<K>, std::equal_to<K>>;
+
+// fnv1a_hash
+
+template<int Bits> struct fnv1a_hash_impl;
+
+template<> struct fnv1a_hash_impl<32>
+{
+    std::size_t operator()( std::string const& s ) const
+    {
+        std::size_t h = 0x811C9DC5u;
+
+        char const * first = s.data();
+        char const * last = first + s.size();
+
+        for( ; first != last; ++first )
+        {
+            h ^= static_cast<unsigned char>( *first );
+            h *= 0x01000193ul;
+        }
+
+        return h;
+    }
+};
+
+template<> struct fnv1a_hash_impl<64>
+{
+    std::size_t operator()( std::string const& s ) const
+    {
+        std::size_t h = 0xCBF29CE484222325ull;
+
+        char const * first = s.data();
+        char const * last = first + s.size();
+
+        for( ; first != last; ++first )
+        {
+            h ^= static_cast<unsigned char>( *first );
+            h *= 0x00000100000001B3ull;
+        }
+
+        return h;
+    }
+};
+
+struct fnv1a_hash: fnv1a_hash_impl< std::numeric_limits<std::size_t>::digits >
+{
+    using is_avalanching = void;
+};
+
+template<class K, class V> using boost_unordered_flat_map_fnv1a =
+    boost::unordered_flat_map<K, V, fnv1a_hash, std::equal_to<K>>;
+
+// slightly bad hash
+
+struct slightly_bad_hash
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string const& s ) const
+    {
+       std::size_t h = s.size();
+
+       for( auto ch: s )
+       {
+         h *= 0x811C9DC4u; // multiplicative factor is even!
+         h += static_cast<std::size_t>( ch );
+       }
+
+       return h;
+    }
+};
+
+template<class K, class V> using boost_unordered_flat_map_slightly_bad_hash =
+    boost::unordered_flat_map<K, V, slightly_bad_hash, std::equal_to<K>>;
+
+// bad hash
+
+struct bad_hash
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string const& s ) const
+    {
+       std::size_t h = s.size();
+
+       for( auto ch: s )
+       {
+         h *= 31;
+         h += static_cast<std::size_t>( ch );
+       }
+
+       return h;
+    }
+};
+
+template<class K, class V> using boost_unordered_flat_map_bad_hash =
+    boost::unordered_flat_map<K, V, bad_hash, std::equal_to<K>>;
+
+//
+
+int main()
+{
+    init_indices();
+
+    test<boost_unordered_flat_map>( "boost::unordered_flat_map" );
+    test<boost_unordered_flat_map_fnv1a>( "boost::unordered_flat_map, FNV-1a" );
+    test<boost_unordered_flat_map_slightly_bad_hash>( "boost::unordered_flat_map, slightly_bad_hash" );
+    test<boost_unordered_flat_map_bad_hash>( "boost::unordered_flat_map, bad_hash" );
+
+    std::cout << "---\n\n";
+
+    for( auto const& x: records )
+    {
+        std::cout << std::setw( 46 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms\n"
+                  << std::setw( 46 ) << "insertion: "
+                      << "probe length " << x.stats_.insertion.probe_length.average << "\n"
+                  << std::setw( 46 ) << "successful lookup: "
+                      << "probe length " << x.stats_.successful_lookup.probe_length.average 
+                      << ", num comparisons " << x.stats_.successful_lookup.num_comparisons.average << "\n"
+                  << std::setw( 46 ) << "unsuccessful lookup: "
+                      << "probe length " << x.stats_.unsuccessful_lookup.probe_length.average 
+                      << ", num comparisons " << x.stats_.unsuccessful_lookup.num_comparisons.average << "\n";
+    }
+}