Larger performance bonuses driven by the semiconductor upturn pushed up first-half wage statistics. Average monthly pay came to about 4.32 million won, up 3.1 percent from a year earlier.

The rise was led by electronics and telecommunications, which includes semiconductor plants. Special payments in that sector surged 66.0 percent in a year, against just 1.8 percent across other sectors, leaving two very different trends inside the same dataset.

The gap by company size

Total monthly pay at workplaces with 300 or more employees averaged 6.497 million won, up 4.8 percent, while those with fewer than 300 averaged 3.818 million won, up only 2.1 percent. Special payments at large firms were about 5.7 times those at smaller ones.

A rising average does not mean most people feel richer. Because bonuses concentrate in particular sectors and firm sizes, the headline growth rate and individual household finances can diverge.

The structure behind the numbers

When memory prices rise, profits swell quickly and bonuses jump with them. In the opposite phase they fall just as fast. That the pay increase came from variable rather than base pay means the downside risk of the next phase comes with it.

Consumption data may show regional variation too. Commercial districts near clustered semiconductor plants move with bonus payment dates, while areas outside cannot expect the same effect.

Sectors where many Chinese self-employed residents in Korea work lie outside the special-payment picture. That is why an announcement of higher average wages does not translate directly into a recovery in their sales.