The part of the sentence "have remained less" is correct and usable in written English.
You can use it to indicate that something has been kept constant for a period of time. For example, "In spite of rising costs, sales of our product have remained less."
Its repertory, meanwhile, has remained less diverse, dedicated to the works of the founder and artistic director Jonathan Hollander.
Though it has handled this metamorphosis skilfully, it has remained less of a force than, well, Morgan Stanley, now the world's pre-eminent investment bank.
The company has been sending its current customers on-screen messages about the filters which have been available since the summer, but voluntary take-up has remained less than 10%.
While much hope has been placed on more active energy users, it has remained less clear what citizens can and are willing to do.
The temporal nature of associations of RC and unintended pregnancy (distinct from the impact of IPV), however, has remained less clear.
Prior to the 1120s there is very little evidence of castles having existed in Scotland, which had remained less politically centralised than in England with the north still ruled by the kings of Norway.
Evidence for physiologically relevant in vivo function of trans RET signaling, however, has remained less conclusive.
What has remained less clear is whether specific critical events during a hospitalization, such as mechanical ventilation, elevate the risk.
Glioblastoma multiforme (GBM) is the most malignant form of human astrocytoma [ 1] and the median survival of GBM has remained less than one year over the past decade.
However, the quality of care for ACS has remained less than optimal in many settings, and recent studies have continued to show a lack of adherence to published guidelines, though improvements have been noted [ 1, 14, 32, 33].
