The phrase "although it has improved" is correct and usable in written English.
You can use it to introduce a contrast or exception regarding a situation that has seen some progress or enhancement.
Example: "The project faced many challenges, although it has improved significantly over the past few months."
Alternatives: "even though it has gotten better" or "despite the improvements made".
WEAKNESSES -- The defense remains a weakness, although it has improved considerably since Tony Dungy's arrival.
There is a definitely a bias against soccer in the media although it has improved.
Oil prices are soaring and the dollar started weakening in December -- although it has improved in the last two weeks -- making imports more expensive.
Unfortunately, hiring also remains very slow, although it has improved a little in recent months from the lows reached during the depths of the recession and credit squeeze.
Land Rover, a perennial cellar dweller, was again at the bottom with 398 problems per 100 vehicles, although it has improved with 40 fewer problems per 100 than last year.
Although it has improved BPI's capital ratios, such a switch of money from deposits to capital erodes future income by reducing lending possibilities.An examination of the BPI group's accounts reveals aggressive accounting practices.
Although it had improved slightly over the last few days, he said it did not matter as long as he continued to hit.
A separate report released today by property firm Hamptons International suggested that aspiring homeowner's ability to buy a property has diminished in the last year although it had improved over the five years since the last election.
Dan's stuff in the first issue was terrible, although it had improved by the second.
The standing shoot had long been her weak point and her hit percentage was well below average in the World Cup field, although it had improved considerably in her later seasons.
This finding was consistent with our study and implies that introduction of the CHSMW has not eliminated the financial barrier to care for the participants, although to some extent it has improved health utilisation amongst the insured.
