diff --git a/geostat.cpp b/geostat.cpp
index 3da0018..05c79f1 100644
--- a/geostat.cpp
+++ b/geostat.cpp
@@ -24,6 +24,8 @@ void show_usage() {
 	std::cout << "\t-k user\t\tuser for opencaching.uk\n";
 	std::cout << "\t-g file\t\tuse specified gpx file\n";
 	std::cout << "\t-q\t\tuse local SQLite file with dump of OC database\n";
+	std::cout << "\t-i timestamp\t\tstart date\n";
+	std::cout << "\t-f timestamp\t\tfinish date\n";
 	std::cout << " * Output:\n";
 	std::cout << "\t-N\t\tcompute stats only for unfound caches (works only with SQLite)\n";
 	std::cout << "\t-Q\t\texclude quiz caches from unfound caches\n";
@@ -46,6 +48,8 @@ int main(int argc, char** argv) {
 	bool use_ocpl_db = 0;
 	bool get_not_found = 0;
 	bool exclude_quiz = 0;
+	std::time_t start_time = 0;
+	std::time_t end_time = std::time(nullptr);
 
 	std::string ocpl_user;
 	std::string ocde_user;
@@ -77,7 +81,7 @@ int main(int argc, char** argv) {
 	if (argc == 1) show_usage();
 
 	int o;
-	while ((o = getopt(argc, argv, "qNQg:o::p:d:u:n:r:k:H:s:m:eth?")) != -1)
+	while ((o = getopt(argc, argv, "qNQg:o::p:d:u:n:r:k:i:f:H:s:m:eth?")) != -1)
 		switch (o) {
 // 			case 'd':
 // 				Debug::set_debug_level(get_num('d',optarg));
@@ -117,6 +121,12 @@ int main(int argc, char** argv) {
 			case 'q':
 				use_ocpl_db = 1;
 				break;
+			case 'i':
+				start_time = get_num('i',optarg);
+				break;
+			case 'f':
+				end_time = get_num('f',optarg);
+				break;
 			case 'N':
 				get_not_found = 1;
 				break;
@@ -232,17 +242,23 @@ int main(int argc, char** argv) {
 	Caches fcc;
 
 	if (!get_not_found) {
-		for (auto& i : cc) {
-			dates[i.date]++;
-			sorted_caches.insert({ i.date_t, &i });
-			if (i.type != "Moving" && i.type != "Own" && (!get_not_found || !exclude_quiz || i.type != "Quiz")) {
-				sorted_fcaches.insert({ i.date_t, &i });
-				fcc.insert(i);
+		for (auto i = cc.begin(); i != cc.end(); ) {
+			if (i->date_t > end_time || i->date_t < start_time) {
+				i = cc.erase(i);
+				continue;
 			}
-			sorted_caches_by_hidden.insert({ i.date_hidden_t, &i });
-			caches_by_fav.push_back(&i);
-			caches_by_fav_perc.push_back(&i);
-			caches_by_finds.push_back(&i);
+			dates[i->date]++;
+			sorted_caches.insert({ i->date_t, &*i });
+			if (i->type != "Moving" && i->type != "Own" && (!get_not_found || !exclude_quiz || i->type != "Quiz")) {
+				sorted_fcaches.insert({ i->date_t, &*i });
+				fcc.insert(*i);
+			}
+			sorted_caches_by_hidden.insert({ i->date_hidden_t, &*i });
+			caches_by_fav.push_back(&*i);
+			caches_by_fav_perc.push_back(&*i);
+			caches_by_finds.push_back(&*i);
+
+			i++;
 		}
 		std::sort(caches_by_fav.begin(), caches_by_fav.end(), [&](const Cache* a, const Cache* b) { return a->fav > b->fav; });
 		std::sort(caches_by_fav_perc.begin(), caches_by_fav_perc.end(), [&](const Cache* a, const Cache* b) { return 1.0 * a->fav / a->founds > 1.0 * b->fav / b->founds; });