How SNP and Green ratings changed since deal signed - see the chart

A chart produced by Stats for Lefties for The National - based on their seat projections extrapolated from a seven-point average of Holyrood opinion polls - shows a steep decline in the SNP’s fortunes since the last Scottish Parliament election.

But it also suggests the Scottish Greens are on the up, predicting they will win three more seats than their current seven.

An average of the party’s performance in polls charting people’s voting intentions in the regional list ballot shows their fortunes virtually unchanged, while a tracker by Ballot Box Scotland shows their constituency voting intention is at a high and on the up.  

Charting some key events in the tumultuous years since the signing of the Bute House Agreement, the graphic shows the impact of events such as the arrests of Nicola Sturgeon (below) and Peter Murrell on support for the SNP.

And it shows how the fortunes of Humza Yousaf’s party took a major tumble in the wake of the row over the Gender Recognition Reform Bill, which was blocked by the UK Government in February 2023.

Their popularity continued to decline when Murrell was first arrested, dipping further after Sturgeon’s arrest.

It also shows the slow but steady increase in support for Labour since the last Holyrood election – overtaking the Tories in early 2022.

However, the chart shows Anas Sarwar’s party is still far from being able to command a majority in Holyrood, putting Scottish Labour one seat behind the SNP.

READ MORE: Patrick Harvie says he will quit as Scottish Greens leader if party bins SNP deal

Anti-Bute House Agreement agitators within the Greens may be given pause for thought by the graphic however, as it appears to show support for their party climbing up – even if grassroots members feel frustrated by compromise.

It could also bolster arguments within the SNP to ditch the Greens, who may argue the party’s present difficulties appear to begin with the row over transgender law reforms, which have since been shelved.

The Bute House Agreement was signed in August 2021 and brought the Scottish Greens into government for the first time.

Among its staunchest defenders is First Minister Humza Yousaf who previously said the deal was “worth its weight in gold”.

READ MORE: SNP members don't want or need vote on Greens deal, says Humza Yousaf 

But it came under intense pressure during last year’s SNP leadership election – in which Yousaf secured a narrow victory over Kate Forbes (below).

The former finance minister wanted to ditch the deal with the Greens, claiming it had moved the party too far to the left, causing them to alienate some voters.

Matters were brought to a head last week when Energy Secretary Mairi McAllan announced she was scrapping a key climate target.

But some believe discontent their leaders have not extracted enough from the SNP on environmental issues.

Elsewhere, the unilateral decision to impose a council tax freeze betrayed a Green manifesto commitment which promised they would “never dictate the levels at which councils can set local taxes from Holyrood”.

A Scottish Greens spokesperson said: “People know every vote for the Scottish Greens is a vote for climate action, for equality and for independence and that is the case we will continue to make.”

An SNP spokesperson said: “As the Tories and Keir Starmer’s Labour Party continue to prioritise protecting Westminster's broken Brexit Britain and ignoring Scotland’s interests, the SNP will continue to make the case for a better future with independence.

“The SNP will continue to improve the lives of people across Scotland with the limited powers currently at our disposal, illustrating that things are better when decisions are made in Scotland, and with the full powers of independence we can create a fairer, more equal country.”