By the end of the first three working days of the year, the U.K.’s top bosses will each have earned on average as much as a typical worker will take home in all of 2018, according to a report.

While the difference in compensation appears stark, it narrowed slightly compared with the previous year, the High Pay Centre and the Chartered Institute of Personnel and Development said on Thursday. The so-called “Fat Cat” study by the groups comes amid growing investor and political unease in the U.K. about high CEO pay.

“The system has worked a little bit better this year,” Stefan Stern, director of the High Pay Center, said by email. “We calculate the typical CEO has to do 32 hours work as opposed to 28” to earn an average worker’s annual salary. The watchdog assumes CEOs work long days.

The past couple of years have been marked by investor revolts against the level of salaries paid to top executives at some London-listed companies including Sky Plc and Pearson Plc (PEARSON-PLC). Other firms adjusted pay packages downwards to avoid protest votes. Adding to the pressure from shareholders, Prime Minister Theresa May has said tackling unfairness in British society is an aim of her government. Two years on, she has yet to introduce any legislation limiting executive pay.

‘Excessive’ gaps

“There are still grossly excessive and unjustifiable gaps between the top and the rest of the workforce,” Stern said in a statement.

The latest calculations were based on an earlier finding by the groups that earnings for CEOs in the U.K.’s benchmark FTSE 100 dropped by a fifth in 2016 to 4.5 million pounds ($5.4 million) annually and another showing a CEO-to-worker pay ratio of 120 to 1. This is far lower than in the U.S., where CEOs of S&P 500 companies received on average $13.1 million in compensation, giving a ratio of 347 to 1, according to the AFL-CIO union.

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C-suite compensation levels have tumbled at some companies following grumbling from shareholders. At WPP Plc, a third of shareholders voted against CEO Martin Sorrell’s 70 million-pound pay package in June 2016. The number of protest votes fell to a little more than a fifth of the total after the advertising company came back last year with a more modest 48 million-pound plan for the executive.

Some firms, such as Legal & General and Aberdeen Asset Management, published pay ratios in their annual reports last year that showed the difference between what their executives were earning compared with the average by employees.

“To ensure this year’s fall in CEO remuneration isn’t just a blip on the consistently upward trend of recent years, it’s crucial that the government keeps high pay and corporate governance reform high on its agenda,” Peter Cheese, chief executive of the CIPD, said in the statement.