SSO vs. XVV ETF Comparison

Comparison of ProShares Ultra S&P500 (SSO) to iShares ESG Screened S&P 500 ETF (XVV)
SSO

ProShares Ultra S&P500

SSO Description

The investment seeks daily investment results, before fees and expenses, that correspond to two times (2x) the daily performance of the S&P 500®. The fund invests in securities and derivatives that ProShare Advisors believes, in combination, should have similar daily return characteristics as two times (2x) the daily return of the index. The index is a measure of large-cap U.S. stock market performance. It is a float-adjusted, market capitalization-weighted index of 500 U.S. operating companies and real estate investment trusts selected through a process. The fund is non-diversified.

Grade (RS Rating)

Last Trade

$95.92

Average Daily Volume

2,118,139

Number of Holdings *

499

* may have additional holdings in another (foreign) market
XVV

iShares ESG Screened S&P 500 ETF

XVV Description The investment seeks to track the investment results of an index composed of large-capitalization U.S. equities while applying screens for company involvement in controversies and controversial business activities. The fund seeks to track the investment results of the S&P 500 Sustainability Screened Index, which measures the performance of the large-capitalization sector of the U.S. equity market while excluding companies involved in controversial business activities and controversies, as determined by S&P Dow Jones Indices LLC. BFA uses a representative sampling indexing strategy to manage the fund. It is non-diversified.

Grade (RS Rating)

Last Trade

$45.89

Average Daily Volume

40,869

Number of Holdings *

443

* may have additional holdings in another (foreign) market
Performance
Period SSO XVV
30 Days 5.41% 3.10%
60 Days 7.88% 4.22%
90 Days 10.71% 5.90%
12 Months 62.05% 32.25%
441 Overlapping Holdings
Symbol Grade Weight in SSO Weight in XVV Overlap
A D 0.05% 0.08% 0.05%
AAPL C 4.58% 7.55% 4.58%
ABBV D 0.39% 0.66% 0.39%
ABNB C 0.08% 0.13% 0.08%
ABT B 0.27% 0.44% 0.27%
ACGL D 0.05% 0.08% 0.05%
ACN C 0.3% 0.49% 0.3%
ADBE C 0.3% 0.49% 0.3%
ADI D 0.14% 0.23% 0.14%
ADM D 0.03% 0.06% 0.03%
ADP B 0.16% 0.27% 0.16%
ADSK A 0.09% 0.15% 0.09%
AFL B 0.08% 0.12% 0.08%
AIG B 0.07% 0.11% 0.07%
AIZ A 0.02% 0.03% 0.02%
AJG B 0.09% 0.14% 0.09%
AKAM D 0.02% 0.03% 0.02%
ALB C 0.02% 0.03% 0.02%
ALGN D 0.02% 0.03% 0.02%
ALL A 0.07% 0.12% 0.07%
ALLE D 0.02% 0.03% 0.02%
AMAT F 0.19% 0.32% 0.19%
AMCR D 0.02% 0.03% 0.02%
AMD F 0.29% 0.48% 0.29%
AME A 0.06% 0.1% 0.06%
AMGN D 0.2% 0.34% 0.2%
AMP A 0.07% 0.12% 0.07%
AMT D 0.12% 0.21% 0.12%
AMZN C 2.53% 4.03% 2.53%
ANET C 0.13% 0.23% 0.13%
ANSS B 0.04% 0.07% 0.04%
AON A 0.11% 0.18% 0.11%
AOS F 0.01% 0.02% 0.01%
APD A 0.09% 0.16% 0.09%
APH A 0.11% 0.19% 0.11%
APTV D 0.02% 0.03% 0.02%
ARE D 0.02% 0.04% 0.02%
ATO A 0.03% 0.05% 0.03%
AVB B 0.04% 0.07% 0.04%
AVGO D 1.03% 1.66% 1.03%
AVY D 0.02% 0.04% 0.02%
AWK D 0.03% 0.06% 0.03%
AXON A 0.06% 0.1% 0.06%
AXP A 0.22% 0.36% 0.22%
AZO C 0.07% 0.12% 0.07%
BAC A 0.42% 0.68% 0.42%
BALL D 0.02% 0.04% 0.02%
BAX D 0.02% 0.04% 0.02%
BBY D 0.02% 0.04% 0.02%
BDX F 0.09% 0.14% 0.09%
BEN C 0.01% 0.01% 0.01%
BG F 0.02% 0.03% 0.02%
BIIB F 0.03% 0.05% 0.03%
BK A 0.08% 0.13% 0.08%
BKNG A 0.22% 0.38% 0.22%
BKR B 0.06% 0.1% 0.06%
BLDR D 0.03% 0.04% 0.03%
BLK C 0.2% 0.31% 0.2%
BMY B 0.15% 0.26% 0.15%
BR A 0.04% 0.06% 0.04%
BRK.A B 1.15% 1.88% 1.15%
BRO B 0.03% 0.06% 0.03%
BSX B 0.17% 0.29% 0.17%
BWA D 0.01% 0.02% 0.01%
BX A 0.17% 0.3% 0.17%
BXP D 0.02% 0.03% 0.02%
C A 0.18% 0.29% 0.18%
CAG D 0.02% 0.03% 0.02%
CAH B 0.04% 0.06% 0.04%
CARR D 0.08% 0.14% 0.08%
CAT B 0.25% 0.41% 0.25%
CB C 0.14% 0.23% 0.14%
CBOE B 0.03% 0.05% 0.03%
CBRE B 0.05% 0.09% 0.05%
CCI D 0.06% 0.1% 0.06%
CCL B 0.03% 0.06% 0.03%
CDNS B 0.11% 0.18% 0.11%
CDW F 0.03% 0.05% 0.03%
CE F 0.01% 0.02% 0.01%
CEG D 0.09% 0.17% 0.09%
CF B 0.02% 0.04% 0.02%
CFG B 0.03% 0.05% 0.03%
CHD B 0.04% 0.06% 0.04%
CHRW C 0.02% 0.03% 0.02%
CHTR C 0.05% 0.08% 0.05%
CI F 0.12% 0.2% 0.12%
CINF A 0.03% 0.05% 0.03%
CL D 0.1% 0.17% 0.1%
CLX B 0.03% 0.05% 0.03%
CMCSA B 0.22% 0.36% 0.22%
CME A 0.11% 0.18% 0.11%
CMG B 0.11% 0.18% 0.11%
CMI A 0.07% 0.11% 0.07%
CNC D 0.04% 0.07% 0.04%
CNP B 0.03% 0.04% 0.03%
COF B 0.09% 0.15% 0.09%
COR B 0.06% 0.09% 0.06%
COST B 0.54% 0.92% 0.54%
CPAY A 0.03% 0.06% 0.03%
CPB D 0.01% 0.02% 0.01%
CPRT A 0.07% 0.11% 0.07%
CPT B 0.02% 0.03% 0.02%
CRL C 0.01% 0.02% 0.01%
CRM B 0.42% 0.71% 0.42%
CRWD B 0.1% 0.18% 0.1%
CSCO B 0.31% 0.5% 0.31%
CSGP D 0.04% 0.07% 0.04%
CSX B 0.09% 0.15% 0.09%
CTAS B 0.1% 0.17% 0.1%
CTLT B 0.01% 0.02% 0.01%
CTSH B 0.05% 0.09% 0.05%
CTVA C 0.05% 0.09% 0.05%
CVS D 0.09% 0.16% 0.09%
CZR F 0.01% 0.02% 0.01%
D C 0.06% 0.11% 0.06%
DAL C 0.05% 0.09% 0.05%
DAY B 0.02% 0.03% 0.02%
DE A 0.14% 0.24% 0.14%
DECK A 0.04% 0.06% 0.04%
DFS B 0.06% 0.1% 0.06%
DG F 0.02% 0.04% 0.02%
DGX A 0.02% 0.04% 0.02%
DHI D 0.06% 0.1% 0.06%
DHR F 0.2% 0.33% 0.2%
DIS B 0.28% 0.45% 0.28%
DLR B 0.07% 0.13% 0.07%
DLTR F 0.02% 0.03% 0.02%
DOC D 0.02% 0.03% 0.02%
DOV A 0.04% 0.06% 0.04%
DOW F 0.04% 0.07% 0.04%
DPZ C 0.02% 0.03% 0.02%
DRI B 0.03% 0.04% 0.03%
DVA B 0.01% 0.02% 0.01%
DXCM D 0.04% 0.06% 0.04%
EA A 0.05% 0.09% 0.05%
EBAY D 0.04% 0.07% 0.04%
ECL D 0.08% 0.13% 0.08%
ED D 0.04% 0.07% 0.04%
EFX F 0.04% 0.07% 0.04%
EIX B 0.04% 0.07% 0.04%
EL F 0.02% 0.03% 0.02%
ELV F 0.12% 0.21% 0.12%
EMR A 0.1% 0.16% 0.1%
ENPH F 0.01% 0.02% 0.01%
EPAM C 0.02% 0.03% 0.02%
EQIX A 0.11% 0.19% 0.11%
EQR B 0.03% 0.06% 0.03%
ES D 0.03% 0.05% 0.03%
ESS B 0.03% 0.04% 0.03%
ETN A 0.19% 0.32% 0.19%
ETR B 0.04% 0.07% 0.04%
EW C 0.05% 0.09% 0.05%
EXC C 0.05% 0.09% 0.05%
EXPD D 0.02% 0.04% 0.02%
EXPE B 0.03% 0.05% 0.03%
EXR D 0.05% 0.08% 0.05%
F C 0.06% 0.09% 0.06%
FAST B 0.06% 0.1% 0.06%
FCX D 0.08% 0.14% 0.08%
FDS B 0.02% 0.04% 0.02%
FDX B 0.09% 0.14% 0.09%
FFIV B 0.02% 0.03% 0.02%
FI A 0.16% 0.27% 0.16%
FICO B 0.07% 0.12% 0.07%
FIS C 0.06% 0.1% 0.06%
FITB A 0.04% 0.07% 0.04%
FMC D 0.01% 0.02% 0.01%
FOX A 0.01% 0.01% 0.01%
FOXA B 0.01% 0.02% 0.01%
FRT B 0.01% 0.02% 0.01%
FSLR F 0.03% 0.04% 0.03%
FTNT C 0.08% 0.13% 0.08%
FTV C 0.04% 0.06% 0.04%
GDDY A 0.03% 0.06% 0.03%
GE D 0.26% 0.42% 0.26%
GEHC F 0.05% 0.08% 0.05%
GEN B 0.02% 0.04% 0.02%
GEV B 0.12% 0.2% 0.12%
GILD C 0.15% 0.24% 0.15%
GIS D 0.05% 0.08% 0.05%
GL B 0.01% 0.02% 0.01%
GLW B 0.05% 0.08% 0.05%
GM B 0.09% 0.14% 0.09%
GNRC B 0.01% 0.02% 0.01%
GOOG C 1.12% 1.77% 1.12%
GOOGL C 1.35% 2.13% 1.35%
GPC D 0.02% 0.04% 0.02%
GPN B 0.04% 0.06% 0.04%
GRMN B 0.04% 0.07% 0.04%
GS A 0.25% 0.41% 0.25%
HAL C 0.04% 0.06% 0.04%
HAS D 0.01% 0.02% 0.01%
HBAN A 0.03% 0.05% 0.03%
HCA F 0.09% 0.13% 0.09%
HD A 0.54% 0.88% 0.54%
HIG B 0.05% 0.08% 0.05%
HLT A 0.08% 0.13% 0.08%
HOLX D 0.02% 0.04% 0.02%
HPE B 0.04% 0.06% 0.04%
HPQ B 0.05% 0.08% 0.05%
HRL D 0.01% 0.02% 0.01%
HSIC B 0.01% 0.02% 0.01%
HST C 0.02% 0.03% 0.02%
HSY F 0.03% 0.06% 0.03%
HUBB B 0.03% 0.05% 0.03%
HUM C 0.04% 0.08% 0.04%
HWM A 0.06% 0.1% 0.06%
ICE C 0.12% 0.2% 0.12%
IDXX F 0.05% 0.07% 0.05%
IEX B 0.02% 0.04% 0.02%
IFF D 0.03% 0.05% 0.03%
INCY C 0.02% 0.02% 0.02%
INTC D 0.14% 0.23% 0.14%
INTU C 0.26% 0.41% 0.26%
INVH D 0.03% 0.04% 0.03%
IP B 0.03% 0.04% 0.03%
IPG D 0.01% 0.02% 0.01%
IQV D 0.04% 0.07% 0.04%
IR B 0.06% 0.09% 0.06%
IRM D 0.05% 0.08% 0.05%
ISRG A 0.25% 0.43% 0.25%
IT C 0.05% 0.09% 0.05%
ITW B 0.1% 0.16% 0.1%
IVZ B 0.01% 0.02% 0.01%
JBHT C 0.02% 0.03% 0.02%
JBL B 0.02% 0.03% 0.02%
JCI C 0.08% 0.12% 0.08%
JKHY D 0.02% 0.03% 0.02%
JNPR F 0.02% 0.03% 0.02%
JPM A 0.93% 1.51% 0.93%
K A 0.03% 0.05% 0.03%
KDP D 0.04% 0.08% 0.04%
KEY B 0.02% 0.04% 0.02%
KEYS A 0.03% 0.07% 0.03%
KHC F 0.04% 0.06% 0.04%
KIM A 0.02% 0.04% 0.02%
KKR A 0.14% 0.23% 0.14%
KLAC D 0.11% 0.19% 0.11%
KMB D 0.06% 0.1% 0.06%
KMI A 0.07% 0.12% 0.07%
KMX B 0.02% 0.03% 0.02%
KO D 0.32% 0.54% 0.32%
KR B 0.05% 0.08% 0.05%
L A 0.02% 0.03% 0.02%
LEN D 0.05% 0.09% 0.05%
LH C 0.03% 0.04% 0.03%
LIN D 0.29% 0.48% 0.29%
LKQ D 0.01% 0.02% 0.01%
LLY F 0.79% 1.29% 0.79%
LOW D 0.21% 0.33% 0.21%
LRCX F 0.12% 0.21% 0.12%
LULU C 0.05% 0.08% 0.05%
LUV C 0.03% 0.04% 0.03%
LVS C 0.02% 0.04% 0.02%
LW C 0.01% 0.02% 0.01%
LYB F 0.03% 0.05% 0.03%
LYV A 0.03% 0.05% 0.03%
MA C 0.58% 0.92% 0.58%
MAA B 0.02% 0.04% 0.02%
MAR B 0.09% 0.14% 0.09%
MAS D 0.02% 0.04% 0.02%
MCD D 0.28% 0.45% 0.28%
MCHP D 0.05% 0.08% 0.05%
MCK B 0.11% 0.18% 0.11%
MCO B 0.1% 0.16% 0.1%
MDLZ F 0.12% 0.19% 0.12%
MDT D 0.15% 0.24% 0.15%
MET A 0.07% 0.11% 0.07%
META D 1.62% 2.68% 1.62%
MGM D 0.01% 0.02% 0.01%
MHK D 0.01% 0.02% 0.01%
MKC D 0.02% 0.04% 0.02%
MKTX D 0.01% 0.02% 0.01%
MLM B 0.05% 0.08% 0.05%
MMC B 0.15% 0.24% 0.15%
MNST C 0.05% 0.08% 0.05%
MOH F 0.02% 0.04% 0.02%
MOS F 0.01% 0.02% 0.01%
MPC D 0.07% 0.12% 0.07%
MPWR F 0.04% 0.06% 0.04%
MRK F 0.33% 0.55% 0.33%
MRNA F 0.02% 0.03% 0.02%
MS A 0.22% 0.37% 0.22%
MSCI C 0.06% 0.1% 0.06%
MSFT F 4.13% 6.67% 4.13%
MSI B 0.11% 0.18% 0.11%
MTB A 0.05% 0.08% 0.05%
MTCH D 0.01% 0.02% 0.01%
MTD D 0.03% 0.05% 0.03%
MU D 0.14% 0.25% 0.14%
NCLH B 0.02% 0.03% 0.02%
NDAQ A 0.04% 0.07% 0.04%
NDSN B 0.02% 0.03% 0.02%
NEE D 0.21% 0.35% 0.21%
NEM D 0.06% 0.11% 0.06%
NFLX A 0.47% 0.84% 0.47%
NKE D 0.12% 0.2% 0.12%
NOW A 0.28% 0.47% 0.28%
NSC B 0.08% 0.13% 0.08%
NTAP C 0.03% 0.06% 0.03%
NTRS A 0.03% 0.05% 0.03%
NUE C 0.05% 0.08% 0.05%
NVDA C 4.67% 7.84% 4.67%
NVR D 0.04% 0.06% 0.04%
NWS B 0.0% 0.01% 0.0%
NWSA B 0.01% 0.02% 0.01%
NXPI D 0.07% 0.13% 0.07%
O D 0.07% 0.11% 0.07%
ODFL B 0.05% 0.09% 0.05%
OKE A 0.09% 0.15% 0.09%
OMC C 0.03% 0.04% 0.03%
ON D 0.04% 0.06% 0.04%
ORCL B 0.39% 0.67% 0.39%
ORLY B 0.09% 0.15% 0.09%
OTIS C 0.05% 0.09% 0.05%
PANW C 0.17% 0.28% 0.17%
PARA C 0.01% 0.01% 0.01%
PAYC B 0.01% 0.02% 0.01%
PAYX C 0.06% 0.1% 0.06%
PCAR B 0.08% 0.13% 0.08%
PEG A 0.06% 0.1% 0.06%
PEP F 0.29% 0.48% 0.29%
PFE D 0.19% 0.31% 0.19%
PFG D 0.02% 0.04% 0.02%
PG A 0.53% 0.88% 0.53%
PGR A 0.2% 0.33% 0.2%
PH A 0.12% 0.19% 0.12%
PHM D 0.04% 0.06% 0.04%
PKG A 0.03% 0.05% 0.03%
PLD D 0.14% 0.23% 0.14%
PNC B 0.11% 0.18% 0.11%
PNR A 0.02% 0.04% 0.02%
PODD C 0.02% 0.04% 0.02%
POOL C 0.02% 0.03% 0.02%
PPG F 0.04% 0.06% 0.04%
PRU A 0.06% 0.1% 0.06%
PSA D 0.07% 0.11% 0.07%
PSX C 0.07% 0.12% 0.07%
PTC A 0.03% 0.05% 0.03%
PWR A 0.06% 0.11% 0.06%
PYPL B 0.12% 0.19% 0.12%
QCOM F 0.24% 0.38% 0.24%
QRVO F 0.01% 0.01% 0.01%
RCL A 0.07% 0.12% 0.07%
REG B 0.02% 0.03% 0.02%
REGN F 0.11% 0.17% 0.11%
RF A 0.03% 0.05% 0.03%
RJF A 0.04% 0.07% 0.04%
RL B 0.01% 0.02% 0.01%
RMD C 0.05% 0.08% 0.05%
ROK B 0.04% 0.07% 0.04%
ROL B 0.02% 0.03% 0.02%
ROP B 0.08% 0.13% 0.08%
ROST C 0.06% 0.1% 0.06%
RSG A 0.06% 0.09% 0.06%
RVTY F 0.02% 0.03% 0.02%
SBAC D 0.03% 0.05% 0.03%
SBUX A 0.15% 0.25% 0.15%
SCHW B 0.16% 0.26% 0.16%
SHW A 0.12% 0.19% 0.12%
SJM D 0.02% 0.03% 0.02%
SLB C 0.08% 0.14% 0.08%
SMCI F 0.01% 0.03% 0.01%
SNA A 0.03% 0.04% 0.03%
SNPS B 0.11% 0.19% 0.11%
SPG B 0.07% 0.12% 0.07%
SPGI C 0.22% 0.36% 0.22%
SRE A 0.08% 0.13% 0.08%
STE F 0.03% 0.05% 0.03%
STLD B 0.03% 0.05% 0.03%
STT A 0.04% 0.06% 0.04%
STX D 0.03% 0.05% 0.03%
STZ D 0.05% 0.08% 0.05%
SW A 0.03% 0.06% 0.03%
SWK D 0.02% 0.03% 0.02%
SWKS F 0.02% 0.03% 0.02%
SYF B 0.03% 0.06% 0.03%
SYK C 0.18% 0.29% 0.18%
SYY B 0.05% 0.08% 0.05%
T A 0.22% 0.36% 0.22%
TAP C 0.01% 0.02% 0.01%
TECH D 0.01% 0.02% 0.01%
TER D 0.02% 0.04% 0.02%
TFC A 0.08% 0.14% 0.08%
TFX F 0.01% 0.02% 0.01%
TGT F 0.09% 0.12% 0.09%
TJX A 0.18% 0.29% 0.18%
TMO F 0.26% 0.43% 0.26%
TMUS B 0.15% 0.25% 0.15%
TPR B 0.02% 0.03% 0.02%
TRGP B 0.06% 0.1% 0.06%
TRMB B 0.02% 0.04% 0.02%
TROW B 0.04% 0.06% 0.04%
TRV B 0.08% 0.13% 0.08%
TSCO D 0.04% 0.06% 0.04%
TSLA B 1.19% 2.05% 1.19%
TSN B 0.02% 0.04% 0.02%
TT A 0.12% 0.2% 0.12%
TTWO A 0.04% 0.07% 0.04%
TXN C 0.25% 0.39% 0.25%
TYL B 0.03% 0.05% 0.03%
UAL A 0.04% 0.07% 0.04%
UBER D 0.21% 0.32% 0.21%
UDR B 0.02% 0.03% 0.02%
UHS D 0.02% 0.03% 0.02%
ULTA F 0.02% 0.03% 0.02%
UNH C 0.73% 1.2% 0.73%
UNP C 0.19% 0.32% 0.19%
UPS C 0.13% 0.21% 0.13%
URI B 0.07% 0.12% 0.07%
USB A 0.1% 0.17% 0.1%
V A 0.69% 1.13% 0.69%
VICI C 0.04% 0.07% 0.04%
VLO C 0.06% 0.1% 0.06%
VLTO D 0.03% 0.06% 0.03%
VMC B 0.05% 0.08% 0.05%
VRSK A 0.05% 0.09% 0.05%
VRSN F 0.02% 0.03% 0.02%
VRTX F 0.16% 0.25% 0.16%
VTR C 0.04% 0.06% 0.04%
VTRS A 0.02% 0.03% 0.02%
VZ C 0.23% 0.39% 0.23%
WAB B 0.05% 0.08% 0.05%
WAT B 0.03% 0.05% 0.03%
WBA F 0.01% 0.01% 0.01%
WBD C 0.03% 0.05% 0.03%
WDC D 0.03% 0.05% 0.03%
WELL A 0.11% 0.17% 0.11%
WFC A 0.34% 0.55% 0.34%
WM A 0.11% 0.18% 0.11%
WMB A 0.09% 0.16% 0.09%
WRB A 0.02% 0.04% 0.02%
WST C 0.03% 0.05% 0.03%
WTW B 0.04% 0.07% 0.04%
WY D 0.03% 0.05% 0.03%
WYNN D 0.01% 0.02% 0.01%
XYL D 0.04% 0.07% 0.04%
YUM B 0.05% 0.08% 0.05%
ZBH C 0.03% 0.05% 0.03%
ZBRA B 0.03% 0.05% 0.03%
ZTS D 0.11% 0.17% 0.11%
SSO Overweight 58 Positions Relative to XVV
Symbol Grade Weight
XOM B 0.71%
JNJ D 0.5%
WMT A 0.49%
CVX A 0.37%
PM B 0.27%
IBM C 0.25%
RTX C 0.21%
HON B 0.2%
PLTR B 0.18%
COP C 0.17%
LMT D 0.15%
BA F 0.14%
MO A 0.13%
SO D 0.13%
DUK C 0.12%
MMM D 0.1%
GD F 0.1%
EOG A 0.1%
NOC D 0.09%
TDG D 0.09%
VST B 0.07%
AEP D 0.07%
GWW B 0.07%
PCG A 0.06%
KVUE A 0.06%
LHX C 0.06%
OXY D 0.05%
DD D 0.05%
DELL C 0.05%
XEL A 0.05%
HES B 0.05%
WEC A 0.04%
FANG D 0.04%
CTRA B 0.03%
NRG B 0.03%
CMS C 0.03%
FE C 0.03%
LDOS C 0.03%
TDY B 0.03%
DVN F 0.03%
AEE A 0.03%
DTE C 0.03%
PPL B 0.03%
EQT B 0.03%
EMN D 0.02%
EVRG A 0.02%
LNT A 0.02%
TXT D 0.02%
MRO B 0.02%
EG C 0.02%
NI A 0.02%
J F 0.02%
HII D 0.01%
APA D 0.01%
SOLV C 0.01%
AES F 0.01%
ERIE D 0.01%
PNW B 0.01%
SSO Underweight 2 Positions Relative to XVV
Symbol Grade Weight
TEL B -0.1%
COO D -0.04%
Compare ETFs