1981/01/01	9.80
1981/01/02	9.80
1981/01/03	9.80
1981/01/04	9.50
1981/01/05	9.80
1981/01/06	9.80
1981/01/07	9.80
1981/01/08	9.50
1981/01/09	9.20
1981/01/10	9.20
1981/01/11	9.20
1981/01/12	9.20
1981/01/13	8.90
1981/01/14	8.90
1981/01/15	8.90
1981/01/16	8.90
1981/01/17	8.60
1981/01/18	8.60
1981/01/19	8.60
1981/01/20	8.30
1981/01/21	8.30
1981/01/22	8.30
1981/01/23	8.30
1981/01/24	8.30
1981/01/25	8.30
1981/01/26	8.30
1981/01/27	8.30
1981/01/28	8.30
1981/01/29	8.30
1981/01/30	8.00
1981/01/31	8.00
1981/02/01	8.00
1981/02/02	7.75
1981/02/03	7.75
1981/02/04	7.75
1981/02/05	7.75
1981/02/06	7.75
1981/02/07	7.50
1981/02/08	7.50
1981/02/09	7.50
1981/02/10	7.50
1981/02/11	7.25
1981/02/12	7.25
1981/02/13	7.25
1981/02/14	7.25
1981/02/15	7.00
1981/02/16	7.00
1981/02/17	6.75
1981/02/18	6.75
1981/02/19	6.75
1981/02/20	6.75
1981/02/21	6.75
1981/02/22	6.75
1981/02/23	6.75
1981/02/24	6.50
1981/02/25	6.50
1981/02/26	6.50
1981/02/27	6.25
1981/02/28	6.25
1981/03/01	6.25
1981/03/02	6.00
1981/03/03	6.00
1981/03/04	6.00
1981/03/05	6.00
1981/03/06	6.00
1981/03/07	6.00
1981/03/08	5.75
1981/03/09	7.00
1981/03/10	6.50
1981/03/11	6.75
1981/03/12	6.50
1981/03/13	6.00
1981/03/14	5.75
1981/03/15	5.75
1981/03/16	5.75
1981/03/17	5.50
1981/03/18	5.50
1981/03/19	5.50
1981/03/20	5.25
1981/03/21	5.25
1981/03/22	5.25
1981/03/23	5.25
1981/03/24	5.25
1981/03/25	5.25
1981/03/26	5.25
1981/03/27	5.75
1981/03/28	5.50
1981/03/29	5.50
1981/03/30	5.25
1981/03/31	5.25
1981/04/01	6.00
1981/04/02	6.25
1981/04/03	5.75
1981/04/04	5.50
1981/04/05	5.25
1981/04/06	5.00
1981/04/07	4.75
1981/04/08	4.75
1981/04/09	4.75
1981/04/10	4.50
1981/04/11	4.00
1981/04/12	6.25
1981/04/13	6.00
1981/04/14	11.60
1981/04/15	10.40
1981/04/16	9.20
1981/04/17	8.60
1981/04/18	11.90
1981/04/19	7.25
1981/04/20	6.00
1981/04/21	5.75
1981/04/22	8.00
1981/04/23	6.50
1981/04/24	5.75
1981/04/25	5.50
1981/04/26	8.30
1981/04/27	11.30
1981/04/28	9.80
1981/04/29	6.75
1981/04/30	7.75
1981/05/01	7.75
1981/05/02	9.20
1981/05/03	21.10
1981/05/04	17.90
1981/05/05	12.20
1981/05/06	8.60
1981/05/07	7.75
1981/05/08	7.00
1981/05/09	7.25
1981/05/10	6.50
1981/05/11	7.00
1981/05/12	10.40
1981/05/13	16.10
1981/05/14	26.90
1981/05/15	21.50
1981/05/16	16.45
1981/05/17	71.30
1981/05/18	40.00
1981/05/19	17.90
1981/05/20	12.50
1981/05/21	188.50
1981/05/22	71.30
1981/05/23	45.30
1981/05/24	30.05
1981/05/25	23.30
1981/05/26	20.30
1981/05/27	16.80
1981/05/28	19.10
1981/05/29	26.00
1981/05/30	23.75
1981/05/31	18.30
1981/06/01	15.40
1981/06/02	27.35
1981/06/03	22.40
1981/06/04	18.70
1981/06/05	17.15
1981/06/06	13.70
1981/06/07	19.50
1981/06/08	18.30
1981/06/09	15.75
1981/06/10	14.35
1981/06/11	13.70
1981/06/12	12.80
1981/06/13	11.60
1981/06/14	11.90
1981/06/15	11.60
1981/06/16	15.75
1981/06/17	14.00
1981/06/18	16.45
1981/06/19	75.30
1981/06/20	51.70
1981/06/21	29.60
1981/06/22	25.10
1981/06/23	40.50
1981/06/24	58.85
1981/06/25	64.40
1981/06/26	49.75
1981/06/27	36.50
1981/06/28	32.50
1981/06/29	27.35
1981/06/30	24.20
1981/07/01	22.85
1981/07/02	20.30
1981/07/03	19.10
1981/07/04	24.65
1981/07/05	33.50
1981/07/06	244.90
1981/07/07	202.40
1981/07/08	146.70
1981/07/09	102.70
1981/07/10	157.70
1981/07/11	114.00
1981/07/12	83.35
1981/07/13	67.30
1981/07/14	63.00
1981/07/15	53.65
1981/07/16	66.50
1981/07/17	60.20
1981/07/18	76.10
1981/07/19	85.90
1981/07/20	85.05
1981/07/21	80.90
1981/07/22	76.10
1981/07/23	67.30
1981/07/24	56.25
1981/07/25	102.70
1981/07/26	846.80
1981/07/27	206.00
1981/07/28	123.00
1981/07/29	106.30
1981/07/30	101.80
1981/07/31	112.00
1981/08/01	92.80
1981/08/02	80.10
1981/08/03	81.70
1981/08/04	87.60
1981/08/05	94.60
1981/08/06	81.70
1981/08/07	73.70
1981/08/08	67.30
1981/08/09	61.60
1981/08/10	57.55
1981/08/11	63.00
1981/08/12	72.10
1981/08/13	60.90
1981/08/14	56.90
1981/08/15	53.00
1981/08/16	51.05
1981/08/17	51.05
1981/08/18	48.45
1981/08/19	46.50
1981/08/20	48.45
1981/08/21	45.90
1981/08/22	43.50
1981/08/23	49.75
1981/08/24	48.45
1981/08/25	43.50
1981/08/26	45.90
1981/08/27	45.30
1981/08/28	99.10
1981/08/29	53.00
1981/08/30	46.50
1981/08/31	43.50
1981/09/01	49.75
1981/09/02	89.30
1981/09/03	126.00
1981/09/04	164.30
1981/09/05	100.90
1981/09/06	131.00
1981/09/07	141.20
1981/09/08	123.00
1981/09/09	81.70
1981/09/10	79.30
1981/09/11	66.50
1981/09/12	61.60
1981/09/13	56.25
1981/09/14	53.00
1981/09/15	49.75
1981/09/16	46.50
1981/09/17	44.70
1981/09/18	41.70
1981/09/19	40.00
1981/09/20	38.50
1981/09/21	37.50
1981/09/22	36.00
1981/09/23	35.00
1981/09/24	33.50
1981/09/25	34.50
1981/09/26	32.50
1981/09/27	32.00
1981/09/28	30.50
1981/09/29	31.00
1981/09/30	30.05
1981/10/01	30.50
1981/10/02	31.00
1981/10/03	29.60
1981/10/04	29.60
1981/10/05	27.80
1981/10/06	37.00
1981/10/07	32.50
1981/10/08	30.50
1981/10/09	31.00
1981/10/10	31.50
1981/10/11	34.50
1981/10/12	32.00
1981/10/13	30.05
1981/10/14	27.80
1981/10/15	26.90
1981/10/16	27.35
1981/10/17	27.80
1981/10/18	33.00
1981/10/19	30.05
1981/10/20	27.35
1981/10/21	27.35
1981/10/22	26.90
1981/10/23	26.45
1981/10/24	31.50
1981/10/25	28.70
1981/10/26	32.00
1981/10/27	27.35
1981/10/28	26.00
1981/10/29	25.55
1981/10/30	25.10
1981/10/31	24.20
1981/11/01	23.75
1981/11/02	23.30
1981/11/03	22.85
1981/11/04	22.40
1981/11/05	22.40
1981/11/06	22.40
1981/11/07	22.85
1981/11/08	22.40
1981/11/09	22.40
1981/11/10	21.50
1981/11/11	21.50
1981/11/12	21.50
1981/11/13	21.50
1981/11/14	21.95
1981/11/15	22.85
1981/11/16	24.20
1981/11/17	31.00
1981/11/18	34.50
1981/11/19	32.50
1981/11/20	23.30
1981/11/21	22.85
1981/11/22	21.95
1981/11/23	21.50
1981/11/24	21.50
1981/11/25	-9999
1981/11/26	-9999
1981/11/27	-9999
1981/11/28	-9999
1981/11/29	-9999
1981/11/30	-9999
1981/12/01	-9999
1981/12/02	-9999
1981/12/03	-9999
1981/12/04	-9999
1981/12/05	-9999
1981/12/06	-9999
1981/12/07	-9999
1981/12/08	-9999
1981/12/09	-9999
1981/12/10	-9999
1981/12/11	-9999
1981/12/12	-9999
1981/12/13	18.30
1981/12/14	20.30
1981/12/15	18.70
1981/12/16	18.30
1981/12/17	17.90
1981/12/18	17.50
1981/12/19	17.50
1981/12/20	17.50
1981/12/21	17.50
1981/12/22	17.50
1981/12/23	17.50
1981/12/24	17.15
1981/12/25	17.50
1981/12/26	17.50
1981/12/27	17.50
1981/12/28	17.15
1981/12/29	16.80
1981/12/30	16.80
1981/12/31	16.80
#===========================================
# Number of observations = 347 / 365
# Average = 33.80