S&P/ASX 200 Index (ASX: XJO) shares are 0.06% lower at 8,722.8 points on Thursday.
Brokers have reduced their ratings on numerous ASX 200 shares this week.
Let's see a sample.

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Viva Energy Group Ltd (ASX: VEA)
The Viva Energy Group share price is $3.21, down 0.2% today.
Over the past month, this ASX 200 energy share has risen 5%.
UBS downgraded Viva Energy shares to a hold rating on Tuesday.
The broker increased its 12-month price target from $2.90 to $3.20.
This implies the stock is fully valued already.
South32 Ltd (ASX: S32)
The South32 share price is $4.54, down 4.3% today.
Over the past month, this ASX 200 mining share has fallen 7%.
Morgan Stanley downgraded South32 shares to a hold rating on Monday.
The broker lifted its 12-month price target from $5.10 to $5.20.
This suggests a potential 15% upside ahead.
TechnologyOne Limited (ASX: TNE)
The TechnologyOne share price is $30.53, down 2.2% today.
Over the past month, this ASX 200 tech share has ascended 7%.
RBC Capital downgraded TechnologyOne shares to a hold rating on Monday.
The broker shaved its 12-month price target from $33 to $32.
This implies a potential 5% upside ahead.
Sandfire Resources Ltd (ASX: SFR)
The Sandfire Resources share price is $20.16, down 4.4% on Thursday.
Over the past month, this ASX 200 copper share has edged 2% lower.
Morgan Stanley downgraded Sandfire Resources shares to a sell rating this week.
The broker raised its price target slightly from $20 to $20.35.
This indicates a potential gain of just 1% over the next year.
Boss Energy Ltd (ASX: BOE)
The Boss Energy share price is $1.22, down 1.8% today.
Over the past month, this S&P/ASX 300 Index (ASX: XKO) uranium share has tumbled 18%.
Jefferies downgraded Boss Energy shares to a hold rating this week.
The broker reduced its 12-month price target from $1.85 to $1.70.
This suggests a potential 39% upside ahead.
Sonic Healthcare Ltd (ASX: SHL)
The Sonic Healthcare share price is $18.35, down 0.1% today.
Over the past month, this ASX 200 healthcare share has fallen 5%.
Goldman Sachs downgraded Sonic Healthcare shares to a hold call this week.
The broker slashed its price target from $23.70 to $19.20.
This suggests potential capital growth of 5% over the next year.