S&P/ASX 200 Index (ASX: XJO) shares are 0.2% higher at 8,714.9 points on Thursday.
Meanwhile, brokers have lifted their ratings on several ASX 200 shares this week.
Let's review.

Image source: Getty Images
CSL Ltd (ASX: CSL)
The CSL share price is $177.29, up 1.7% today.
Over the past month, this ASX 200 healthcare share has ripped 32%.
RBC Capital upgraded CSL shares to a buy rating on Tuesday.
The broker raised its 12-month price target substantially from $148 to $213.
This implies a potential 20% upside ahead.
National Australia Bank Ltd (ASX: NAB)
The NAB share price is $38.91, up 2.3% today.
Over the past month, this ASX 200 bank share has fallen 1%.
Citi upgraded NAB shares to a buy rating yesterday.
The broker increased its 12-month price target from $40 to $42.10.
This suggests a potential 8% upside ahead.
Lottery Corporation Ltd (ASX: TLC)
The Lottery Corporation share price is $4.86, up 0.7% today.
Over the past month, this ASX 200 consumer discretionary share has fallen 9%.
Morgans upgraded Lottery Corporation shares to a buy call today.
The broker reduced its 12-month price target from $5.60 to $5.40.
This implies a potential 11% upside ahead.
Ramsay Health Care Ltd (ASX: RHC)
The Ramsay Health Care share price is $55.06, up 0.4% today.
Over the past month, this ASX 200 healthcare share has risen 23%.
RBC Capital upgraded Ramsay Health Care shares to a buy call this week.
The broker increased its 12-month price target significantly from $52 to $68.
This indicates potential capital gains of 23% over the next year.
Challenger Ltd (ASX: CGF)
The Challenger share price is $10.09, down 1.9% today.
Over the past month, this ASX 200 financial share has increased 4%.
UBS upgraded Challenger shares to a buy rating with a $11.50 price target.
This suggests a potential 14% upside ahead.
James Hardie Industries Plc (ASX: JHX)
The James Hardie share price is $37.38, up 0.2% today.
Over the past month, this ASX 200 materials share has fallen 15%.
Morgans upgraded James Hardie shares to an accumulate rating yesterday.
The broker shaved its 12-month price target from $45 to $43.
This suggests potential capital growth of 15% over the next year.
Morgans said:
The positive company story and the growth trajectory are only partially offset by the tough macro, a 75bps rise in the 30-year mortgage rate over the past six months, and a peer multiple de-rate.
On this basis we upgrade to an Accumulate rating, whilst moderating our target price to A$43.00 (from A$45.00).