FICO states that there are two criteria under which a new credit card application is measured.
New Credit will include the duration between your old and new credit account as well as your recent application. It will make up almost 10% of your FICO scores. The credit history length will also come into effect and it would incorporate the oldest credit account age and your newest credit account age which makes up almost 15% of your credit scores.
Based on this 25% of your FICO scores, your credit scores for a year will go down by almost 5 points or less than that. It will also depend on your credit habits and also on your annual income.