XBI · WMTMT

Dec 31Mar 13May 21Aug 3Oct 9

Breadth

82 / 157

stocks rose with the index

Concentration

30%

of the gain from MRNA, TWST, IOVA

Biggest driver

MRNA +3.93

MODERNA INC, +662.97%

Biggest drag

ALNY −2.22

ALNYLAM PHARMACEUTICALS INC, −41.49%

What drove it

157 members · drivers first · YTD · residual 968.1bp exceeds 60bp gate

The XBI rose 26.10% (+31.82 pts) so far this year, but 75 of 157 members went the other way. MRNA and TWST carried the tape higher, accounting for 30% of the gain.

Read the latest market-close note: Goldman and Microsoft Push the Dow to a Large Gain While Telecoms Sink Communication Services

+51.6 pts from 78 gainers−20.9 pts from 79 losers

net +31.8 pts · gainers outweigh losers 2.5 to 1

Stock

Points

Return

XBIsum of all 157 stocks

+31.8

+26.10%

MRNAMODERNA INC

+3.9

+662.97%

TWSTTWIST BIOSCIENCE CORP

+3.3

+403.72%

IOVAIOVANCE BIOTHERAPEUTICS INC

+2.4

+435.53%

IBRXIMMUNITYBIO INC

+2.1

+430.81%

ERASERASCA INC

+1.9

+330.91%

GRALGRAIL INC

+1.8

+64.25%

NTRANATERA INC

+1.7

+74.91%

CDNACAREDX INC

+1.5

+237.95%

KODKODIAK SCIENCES INC

+1.5

+257.19%

SYRESPYRE THERAPEUTICS INC

+1.5

+161.57%

CRSPCRISPR THERAPEUTICS AG

+1.4

+1.81%

TGTXTG THERAPEUTICS INC

+1.4

+85.74%

VCYTVERACYTE INC

+1.2

+7.43%

BEAMBEAM THERAPEUTICS INC

+1.2

−7.29%

KRYSKRYSTAL BIOTECH INC

+1.2

+34.51%

127 othersclick to expand the full index

+15.5

STOKSTOKE THERAPEUTICS INC

−0.4

−22.05%

SPRYARS PHARMACEUTICALS INC

−0.4

−63.69%

MIRMMIRUM PHARMACEUTICALS INC

−0.4

+8.89%

ACADACADIA PHARMACEUTICALS INC

−0.5

−25.95%

NKTRNEKTAR THERAPEUTICS

−0.5

−45.85%

SMMTSUMMIT THERAPEUTICS INC

−0.5

+0.57%

CAPRCAPRICOR THERAPEUTICS INC

−0.5

−72.87%

ADMAADMA BIOLOGICS INC

−0.6

−43.20%

SRPTSAREPTA THERAPEUTICS INC

−0.7

−17.05%

PRAXPRAXIS PRECISION MEDICINES I

−0.8

−11.83%

VERAVERA THERAPEUTICS INC

−0.8

−41.00%

IONSIONIS PHARMACEUTICALS INC

−1.4

−42.76%

INSMINSMED INC

−1.5

−42.20%

QUREUNIQURE NV

−1.5

−5.60%

ALNYALNYLAM PHARMACEUTICALS INC

−2.2

−41.49%

Cap weighting, illustrated

KYMERA THERAPEUTICS INC and SAGIMET BIOSCIENCES INC A moved almost identically (+44.45% vs +50.84%), yet KYMR moved the XBI 85.5× as much. In a cap-weighted index, the bigger company's weight turns the same percentage move into far more points.

Attribution map

slicing the +31.82 pt move · cell size = points contributed · color = direction, intensity = return

MRNA+3.9 pts(+663.0%)

TWST+3.3 pts(+403.7%)

IOVA+2.4 pts(+435.5%)

ALNY−2.2 pts(−41.5%)

IBRX+2.1 pts(+430.8%)

ERAS+1.9 pts(+330.9%)

GRAL+1.8 pts(+64.2%)

NTRA+1.7 pts(+74.9%)

QURE−1.5 pts(−5.6%)

CDNA+1.5 pts

KOD+1.5 pts

INSM−1.5 pts

SYRE+1.5 pts(+161.6%)

CRSP+1.4 pts(+1.8%)

IONS−1.4 pts(−42.8%)

TGTX+1.4 pts

VCYT+1.2 pts

BEAM

KRYS+1.2 pts(+34.5%)

ORKA+1.2 pts(+170.9%)

SLS+1.1 pts

RVMD+1.1 pts

PTGX

HALO

NVAX+0.9 pts

DNTH

PURR

KYMR+0.9 pts

TVTX+0.8 pts

VERA

PRAX

ROIV

NTLA+0.7 pts

EXEL+0.7 pts

PVLA+0.7 pts

PCVX

ABSI

ADMA

AMGN+0.6 pts

INCY

CAPR

TNGX

GILD

SMMT

NKTR

ACAD

MIRM

SPRY

STOK

BMRN

LXEO

XNCR

ARDX

OLMA

CMPX

DNLI

RXRX

IMVT

TYRA

TRAX

Concentration curve

cumulative share of the +31.82 pt move · sorted by contribution

When they drove it

cumulative points through the period

Breadth

member returns, this period

−100%+100%+300%+500%

From −81.51% (CMPX) to +662.97% (MRNA). Equal-weight, the XBI would be +29.63% vs the actual +26.10%; the gap is what cap weighting did.

By sector

point contribution · sums to +31.82 pts

-157

+30.7

The year, session by session

every trading day of 2026 · hover for the move

JANFEBMARAPRMAYJUNJULAUGSEPOCT

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SPDR S&P Biotech ETF

What drove it

Attribution map

Concentration curve

When they drove it

Breadth

By sector

The year, session by session

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