Shoppers visited stores in central Athens yesterday as a number of retailers began offering discounts before of the sales period in a bid to get a head start on the competition. The summer sales period is scheduled to start July 15. Data released last week showed that retail spending fell sharply in April as households trimmed food and shopping bills in order to get by. Meanwhile, other survey results showed an improvement in economic sentiment in the last few months. The Association of Chief Executive Officers said yesterday its business sentiment index among CEO’s rose to 107 units in the second quarter of the year from 94 in the first quarter. CEOs of smaller and medium-sized companies were less optimistic than their peers at large corporations, the survey said.