The index dropped from 81.9 to 81.2 in June with the decline entirely spurred by a decline in the expectations index. The expectations index, which "normally mirrors changes in equity prices and seasonally adjusted gasoline prices," according to Capital Economics, slipped from 73.7 to 72.2 in June.
"We suspect that a rise in the latter explains the decline, as stock markets have reached record high over the past week," said Capital Economics economist Amna Asaf.
While expectations turned slightly sour in June, the current conditions index experienced an increase from 94.5 to 95.4.
As such, Capital Economics expects strengthening confidence over the next few months.
While gas prices have impacted expectations and may push consumption growth lower than the first quarter's 3.1 percent, according to Capital Economics, other economic fundamentals showed promise in June.
The University of Michigan index revealed rising equity prices, improving labor markets, and declines in the cost of household borrowing.