The U.S. Consumer Sentiment Index released by the University of Michigan (UM) Surveys of Consumers Friday was 98.2 in June, virtually unchanged from 98.0 in May and 98.8 in April.

Meanwhile, the Current Conditions Index was 116.5 in June, up from 111.8 in May and 112.4 in last June; and the Expectations Index was 86.3, down from 89.1 in May but up from 83.8 in last June.

Consumer sentiment has been virtually unchanged for the past three months, and has shown only small and insignificant variations during the past 18 months.

Experts attribute the situation to widespread expectations for income and job gains.

According to June survey, U.S. consumers anticipate an annual gain of 2.5 percent in household incomes, up from 1.6 percent in May and the highest rate of increases in incomes since 2008. Consumers aged below 45 anticipate income gains of 4.6 percent in June.

When describing how their current finances had changed, 47 percent of consumers report income gains, the highest rate since mid-1966. Just one-in-10 households in the June survey anticipate that their financial situation would worsen during the year ahead.

The fact is consumers' expectation for income and job gains has offset their expectation for rising inflation and interest rate.

U.S. consumers in June expect an inflation rate of 3.0 percent for the year ahead due to rising energy prices, up from 2.6 percent in last June, and are anticipating an annual inflation rate of 2.6 percent in the next five years, slightly above the 2.5 percent recorded in the prior five months.

Consumers still anticipate rising interest rates during the year ahead. But they do not view rising interest rate as a barrier to economic growth during the year ahead. Importantly, consumers expect the economy to continue to produce new jobs and for the unemployment rate to inch down from its already low level.

"The potential impact of tariffs on the domestic economy was spontaneously cited by one-in-four consumers, with most expecting a negative impact on the domestic economy," said UM economist Richard Curtin, director of the surveys.

"While tariffs may have a direct impact on only a very small portion of overall GDP, the negative impact could quickly generalize and produce a widespread decline in consumer confidence and optimism," Curtin added.

The UM Surveys of Consumers is a rotating panel survey based on a nationally representative sample that gives each household in the coterminous U.S. an equal probability of being selected.