I think there is something very strange here.
There is no-way values of properties can be down by nearly 75%. That would mean builders were selling property for less than the building material costs and that just isn´t likely or adviseable.
However, there was a report out last week which claimed SALES were down by 74% https://www.spanishpropertyinsight.com/forums/viewtopic.php?t=3217
I suspect that the intrepid reporter at the Telegraph must have got her VALUES and SALES figures confused. It seems to me that her figure of “nearly 75% reduction in values” is a little close to close to “nearly 74% reduction in sales” as the largest 7 developers have confirmed last week.
Other than this I cannot possibly account for such a ridiculous statement, though it would be good if Mark Could throw some light on the subject.