PERF: benchmark to_datetime quarter parsing

Author: qwhelan

asv_bench/benchmarks/timeseries.py

@@ -338,6 +338,15 @@ def time_different_offset(self):
         to_datetime(self.diff_offset)
 
 
+class ToDatetimeFormatQuarters(object):
+
+    def setup(self):
+        self.s = Series(['2Q2005', '2Q05', '2005Q1', '05Q1'] * 10000)
+
+    def time_infer_quarter(self):
+        to_datetime(self.s)
+
+
 class ToDatetimeFormat(object):
 
     def setup(self):