In cost systems, costs are generally assumed to exhibit symmetric behavior regardless of the direction of change—increase or decrease—in cost drivers. However, recent research (Anderson et al. 2003) analyzing selling, general, and administrative (SG&A) expense behavior discovered asymmetric cost behavior. This study analyzed the cost behavior of manufacturing cost components and SG&A expenses over a 22-year period for 372 Korean manufacturing firms. The results showed that while material costs and labor costs exhibited symmetric behavior regardless of the direction of sales changes, manufacturing overhead displayed downward sticky cost behavior. SG&A expenses also exhibited downward sticky behavior, consistent with prior research findings. When sales increases or decreases persisted over a certain period, the downward stickiness of most manufacturing cost components and SG&A expenses was alleviated, which is a meaningful result demonstrating that when the time horizon for adjusting resource inputs is extended, committed costs can be converted into variable costs. This study presents the first analytical findings on the cost behavior of manufacturing costs in manufacturing firms.