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顧客與供應商關係與成本結構
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Moreover, we also investigate whether customer concentration has any effect on the
cost stickiness behavior of operating costs. Operating costs (OC) are the expenses which
are related to the operation of a company. Operating costs of a manufacturing company
include SG&A costs, research and development expenses, etc., which are also related to
production.
Column (3) of Table 5 reports the result with full control variable. The coefficient on
∆
ln(Sale)
is 0.42126 (
t
-statistic = 63.81), positively significant at the 0.1% level, which is
as expected that operating cost (
OC
) are positively correlated to the sales revenue. The
estimated coefficient, 0.42126 indicates that
OC
increase 0.42% per 1% increase in sales
revenue. The coefficient on ∆
ln(Sale)*Dec
is -0.16485 (
t
-statistic = -13.43), significantly
negative at the 0.1% level, which is consistent with the notion that
OC
is sticky. The
combined value of these two coefficients on ∆ln
(Sale)
and ∆ln
(Sale)
*
Dec
is 0.25641,
indicating that
OC
decreases only 0.2564% per 1% decrease in sales revenue. When
customer concentration (
CC
) is included in the model, the coefficient on our variable of
interest,
CC*∆ln(Sale)*Dec
, is 0.35789 (
t
-statistic = 4.68). The result shows that for
companies with more concentrated customers,
OC
is less sticky when sales decrease.