By Reuters Staff (Adds more details from filing) Jan 25 (Reuters) - Survey-software seller Qualtrics International Inc, owned by business software group SAP , is aiming for a valuation of roughly $15 billion in its U.S. initial public offering, as it tees up for a blockbuster market debut. Qualtrics’ plan adds to the IPO frenzy as U.S. capital markets hover around record highs, with investors ever so hungry for high-growth tech stocks. Companies raised about $168 billion in the United States in 2020, according to Dealogic data. In comparison, companies raised $108 billion in 1999, which previously held the record for capital raised through new issues.