3011

Monthly sr?° Levels in Powdered Milk from Perry, New York
Since April 1954, 5-pound cans of powdered whole milk have

been sent to HASL each week from a milk powdering plant at Perry, New
York.

Table 8 summarizes 1956 data in puc Sr?°/eram Ca.
are graphed in Figure 8.

The data

The values through December 1955 represent

monthly averages of weekly samples, the error term representing one
standard deviation from the mean.

The monthly values for the year

1956 represent one analysis and a standard error of counting since
the weekly samples were pooled each month.

Starting January 1957,

the monthly composites have been analyzed in replicate, the values
thus being an average and the error term one standard deviation from
the mean,

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