...Koppers Holdings Inc.'s (Koppers) credit profile reflects its leading positions in the North American wood railroad crosstie and wood-treating chemicals industries, its relatively stable earnings generated by the Railroad and Utility Products and Services (RUPS) segment, which benefits from a significant portion of sales under long-term contracts, and the company's solid credit metrics for the rating including its improving leverage driven by its earnings increase and good free cash flow generation. The company's good liquidity also supports the ratings. Koppers' credit profile is constrained by its narrow business focus in the wood preservation industry, its exposure to raw material price fluctuations and the cyclical end markets including construction, aluminum, steel and tires, and its ongoing spending on shareholder returns and business acquisitions, which may limit improvement of its credit metrics. The company's environmental liabilities, although currently manageable, could adversely...