18 
BULLETIN 1411, U. S. DEPARTMENT OF AGRICULTURE 
greater than that of northern potatoes, whose index is only 3.2 per 
cent. The meaning of these figures is that the average week-to- 
week change in wholesale price throughout the market season for 
lettuce is 26.4 per cent of the mean price for the lettuce season, whereas 
for potatoes the mean week-to-week change in wholesale price is 
only 3.2 per cent of the average price for the potato season. 
INDEX OF VARIABILITY OF WHOLESALE PRICES 
THIRTEEN LEADING FRUITS AND VEGETABLES 
10 
PER CENT 
15 
20 
25 
30 
i T""^ 
LOW VARIABILITY 
N. POTATOES 
BOXED APPLES - - 
SWEET POTATOES 
BARRELED APPLES 
CALIF. ORANGES -- 
MEDIUM VARIABILITY 
S. POTA TOES 
N. CABBAGE 
YELLOW ONIONS -- 
HIGH VARIABILITY 
W. LETTUCE 
CANTALOUPES 
PEACHES 
S. CABBAGE 
E. LETTUCE 
Fig. 8.— Highly perishable and seasonal commodities hare high variability in wholesale price, while 
staples have low variability. Wholesale price changes, however, do not appear to influence the jobbers' 
portion of the retail sale 
Naturally a wide range exists in the indices, as shown in Table 7. 
The commodities are seen to fall rather definitely into three dis- 
tinct groups. Five of the articles have a distinctly low index — less 
than 10 per cent. Three of them are in a medium group, with in- 
dices between 10 and 15 per cent. With the remaining five articles 
there is high variability, near or above 20 per cent. Graphic com- 
parison of the three groups is afforded in Figure 8. 
Table 7. — Index of variability in wholesale price, New York metropolitan area, 
February, 1928, to May, 1924 ! 
Low 
Per cent 
Medium 
Per cent 
High 
Per cent 
Northern potatoes 
3.2 
4.6 
5.4 
8.0 
9.2 
Southern potatoes 
Northern cabbage 
11.8 
12.8 
13.5 
"Western lettuce 
Cantaloupes 
Peaches 
Southern cabbage 
Eastern lettuce 
19.6 
22. 3 
Sweetpotatoes... .. _. 
24.1 
Barreled apples 
California oranges 
25.9 
26.4 
White onions omitted because of lack of coptinuous price quotations. 
This grouping of commodities according to variability in wholesale 
prices agrees in general with their relative perishability. The low- 
variability group includes the more staple articles which keep fairly 
well. These may be supplied to the market or withheld from it 
according to its demands, so that variation between supply and 
