Footwear and casual clothing designer and marketer Vans Inc on Thursday posted a sharp fall in first quarter net profit amid sliding same-store sales and a poor performance by its skateparks. The California-based company said net income slumped to $5.4 million from $11.3m in the year-ago period and although sales rose 5.5 per cent to $124.6m from $118.1m, same-store sales fell 4.9 per cent.