Quarter	Thousands, Seasonally adjusted
1991-03-31	33000
1991-06-30	31000
1991-09-30	7000
1991-12-31	12000
1992-03-31	10000
1992-06-30	10000
1992-09-30	10000
1992-12-31	8000
1993-03-31	7000
1993-06-30	9367
1993-09-30	8100
1993-12-31	9543
1994-03-31	19823
1994-06-30	13321
1994-09-30	8114
1994-12-31	11835
1995-03-31	12836
1995-06-30	11384
1995-09-30	12345
1995-12-31	14178
1996-03-31	17933
1996-06-30	11787
1996-09-30	15993
1996-12-31	18836
1997-03-31	26155
1997-06-30	33973
1997-09-30	25546
1997-12-31	29937
1998-03-31	34289
1998-06-30	31501
1998-09-30	30586
1998-12-31	31275
1999-03-31	18689
1999-06-30	18847
1999-09-30	22581
1999-12-31	21831
2000-03-31	18046
2000-06-30	19300
2000-09-30	16847
2000-12-31	13405
2001-03-31	15995
2001-06-30	17097
2001-09-30	18207
2001-12-31	15692
2002-03-31	17897
2002-06-30	25077
2002-09-30	31438
2002-12-31	37239
2003-03-31	41037
2003-06-30	41858
2003-09-30	52922
2003-12-31	66643
2004-03-31	63736
2004-06-30	59666
2004-09-30	44728
2004-12-31	35590
2005-03-31	37231
2005-06-30	54069
2005-09-30	50393
2005-12-31	67376
2006-03-31	71342
2006-06-30	66036
2006-09-30	72716
2006-12-31	81823
2007-03-31	74738
2007-06-30	74361
2007-09-30	72990
2007-12-31	43489
2008-03-31	25810
2008-06-30	11357
2008-09-30	5323
2008-12-31	3435
2009-03-31	5978
2009-06-30	5909
2009-09-30	5678
2009-12-31	6233
2010-03-31	7335
2010-06-30	9707
2010-09-30	12442
2010-12-31	14231
2011-03-31	14812
2011-06-30	15446
2011-09-30	15829
2011-12-31	14996
2012-03-31	12477
2012-06-30	10717
2012-09-30	9429
2012-12-31	10905
2013-03-31	9713
2013-06-30	11505
2013-09-30	12078
2013-12-31	11628
2014-03-31	12802
2014-06-30	14315
2014-09-30	13394
2014-12-31	12976
2015-03-31	13675
2015-06-30	11827
2015-09-30	11545
2015-12-31	11960
2016-03-31	12444
2016-06-30	8292
2016-09-30	6969
2016-12-31	8000
2017-03-31	7260
2017-06-30	8100
2017-09-30	9641
2017-12-31	8117
2018-03-31	9222
2018-06-30	10719
2018-09-30	9697
2018-12-31	9988
2019-03-31	8763
2019-06-30	9463
2019-09-30	8980
2019-12-31	8849
2020-03-31	9684
2020-06-30	4097
2020-09-30	13347
2020-12-31	18449
2021-03-31	18584
2021-06-30	20296
2021-09-30	13212
2021-12-31	10934
2022-03-31	10551
2022-06-30	10636
2022-09-30	8811
2022-12-31	5964
2023-03-31	7333
2023-06-30	7585
2023-09-30	8943
2023-12-31	7911