Last month, Google's share of the US search market dropped below 75 per cent for the first time, according to StatCounter Global Stats.
Since Firefox switched its search engine allegiance from Google to Yahoo at the start of December 2014, Yahoo has gained a further 2.3 per cent of the US search market. It now has a total share of 10.9 per cent.
Meanwhile, Google's grip over the US market has slowly loosened since November. Over three months its share of 77.3 per cent has dropped to an all-time low of 74.8 per cent. During December, the month in which Firefox switched allegiance to Yahoo, Google's share dropped dramatically by 2.1 per cent.
What about Bing?
Despite Yahoo's recent headway in the US search market, Bing has remained the US's second-favourite search engine. In November Bing had a 12.1 per cent share of the market, which increased to 12.5 per cent in December, and then dropped ever so slightly to 12.4 per cent in January.
Bing is also the second-favourite search engine in the UK, where its market share has steadily increased since September. Yahoo's share of the UK search market continues to oscillate, currently at its lowest since June 2014.
Are any Firefox users switching back to Google?
Towards the end of January, Google started to encourage Firefox users to shun Yahoo and switch their defaults browsers back to Google.
When Firefox users manually visited Google, a message appeared just below the search bar, which read: "Get to Google faster. Make Google your default search engine." The "Yes" and "No" options were worded "Sure" and "No thanks", in typical Google fashion.
Google also sent out a tweet that directed Firefox users to a specially-designed page, which instructed them on how to change their browser's default back to Google.