Tabulated by year below are:

• precipitation P (m water equivalent until 30 September of the year shown) at a low level station near Blue Glacier (Forks, Washington);
• equilibrium line altitude ELA (m above NGVD 1929, which is approximate sea level);
• glacier length L (m from head of the glacier);
• three mass balance series (m water equivalent until 30 September of the year shown):
  - b' from 1956 to 1986 was published by Armstrong (1989) based on stake measurements and probing discussed previously. Those in parentheses were estimated by Armstrong. Since 1986 we have estimated the annual balance from late season measurements of the ELA and these are marked with an asterisk (*).
  - b₁ series is created by subtracting a single constant from each b' value so that the series is consistent with the 1957-95 mass change derived from the mapping.
  - b₂ series is created by subtracting one constant from each value between 1957-87 and another is subtracted between 1987-95 so that the series is consistent with both the 1957-87 and 1987-95 mass changes.

	YEAR	P	ELA	L	b'	b_2	b_1

	1956	3.3	1530		1.39	1.15	1.02
	1957	2.8		4210	(-1.10)	-1.34	-1.47
	1958	2.5	2100		-1.66	-1.90	-2.03
	1959	3.2	1725	4192	-0.06	-0.30	-0.43
	1960	2.8	1730	4189	-0.04	-0.28	-0.41
	1961	3.6	1675	4191	0.71	0.47	0.34
	1962	2.6	1700	4194	0.45	0.21	0.08
	1963	2.7	1900	4194	-0.34	-0.58	-0.71
	1964	3.4	1645	4194	0.87	0.63	0.50
	1965	2.4	1950	4199	-0.32	-0.56	-0.69
	1966	2.8	1655		0.58	0.34	0.21
	1967	3.4	1675	4208	0.58	0.34	0.21
	1968	3.9	1850		0.27	0.03	-0.10
	1969	3.3	1660		0.95	0.71	0.58
	1970	2.3	1825	4218	-0.15	-0.39	-0.52
	1971	3.2	1580	4224	1.39	1.15	1.02
	1972	3.2	1600		0.64	0.40	0.27
	1973	2.7	1730		0.10	-0.14	-0.27
	1974	4.1	1505		2.24	2.00	1.87
	1975	2.7	1620	4273	0.91	0.67	0.54
	1976	4.1		4308	(1.66)	1.42	1.29
	1977	2.2		4324	(-1.00)	-1.24	-1.37
	1978	2.9		4347	(0.75)	0.51	0.38
	1979	2.2	1970	4350	-0.91	-1.15	-1.28
	1980	3.4	2020	4353	-1.37	-1.61	-1.74
	1981	3.2	2030	4352	-1.07	-1.31	-1.44
	1982	3.5	1645	4345	0.99	0.75	0.62
	1983	3.7	1610	4349	1.58	1.34	1.21
	1984	3.3	1660	4351	0.73	0.49	0.36
	1985	2.4	1665	4353	0.66	0.42	0.29
	1986	2.9	1910	4352	-0.68	-0.92	-1.05
	1987	2.7	1750	4341	0.01*	-0.79	-0.37
	1988	2.5	1625	4313	1.01*	0.22	0.64
	1989	2.6	1725	4301	0.15*	-0.64	-0.22
	1990	2.7	1850	4289	-0.39*	-1.18	-0.76
	1991	3.4	1750	4275	0.01*	-0.79	-0.37
	1992	2.8	1850	4233	-0.39*	-1.18	-0.76
	1993	2.4	1900	4226	-0.55*	-1.35	-0.93
	1994	2.8	2050	4201	-0.96*	-1.75	-1.33
	1995	3.3	1650	4209	0.78*	-0.01	0.41
	1996	3.5	1750	4201	0.01*	-0.79	-0.37
	1997		1700	4186	0.31*	-0.49	-0.06

1998 bn -0.88 (Conway, June 2001)

1999 ELA 1500

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