Normal gain is a term used in a variety of industries to describe the expected amount of growth or increase in a particular metric. Synonyms for normal gain could include steady growth, typical increase, regular progress, expected advancement, or standard improvement. Other synonyms might include habitual expansion, predictable expansion, common development, or customary gain. Depending on the context, additional synonyms for normal gain could include stable rise, consistent gain, gradual increase, or standard advancement. Ultimately, the precise synonym for normal gain will depend on the industry, metric, and context in which the term is being used.