7 Employees’ information (continued)
Share based payments
Details of share options outstanding under each of the Group’s schemes is set out below:
1 Shares ordinarily exercised immediately on vested date.
2 Relates to non-vested SIP free shares, partnership shares and matching shares granted.
The weighted average exercise prices of the outstanding options and outstanding options exercisable at 31 December 2019 for the Share Option Schemes were 304 pence and 309 pence respectively (2018: 302 pence and 309 pence respectively) and for the Save As You Earn Scheme were 77 pence and 278 respectively (2018: 224 pence and nil respectively).
A Share Option Schemes
Options to subscribe for ordinary shares may be awarded under the intu properties plc Company Share Option Plan and the intu properties plc Non-approved Executive Share Option Scheme.
Such options may not be exercised within three years of grant or before the satisfaction or waiver of any applicable performance conditions and will be forfeited if the employee leaves the Group before their options become capable of exercise, except in certain circumstances. The options will lapse if not exercised within 10 years of the date of grant.
B Performance Share Plan (PSP)
The Company operates a PSP for eligible employees at the discretion of the Remuneration Committee
Awards may be made in the form of nil cost options, a conditional share award or prior to April 2019, a joint share ownership award and fixed-value zero-cost option, and eligible employees may be granted any combination of such awards subject to any individual limits.
The 2020 PSP awards will vest based on (i) 50 per cent of each award – relative Total Shareholder Return vs a bespoke real estate sector peer group (this group being expanded from the very small groups used previously) and (ii) 50 per cent of each award – intu’s Total Property Return vs the MSCI UK Shopping Centre benchmark. This mix of metrics represents a change from the 2019 awards which were based 50 per cent each on relative and absolute TSR targets subject to a Remuneration Committee-operated discretionary assessment of underlying financial performance. It is intended that awards will vest three years following grant (with an additional two year post vesting holding period applying to the net number of shares that vest if the Remuneration Committee considers it appropriate to apply such additional condition).
C Bonus Share Scheme (Bonus Scheme)
Under the Company’s Bonus Scheme, shares may be awarded on a deferred basis as part of a bonus award (Deferred Share Awards).
Deferred Share Awards comprise Restricted Shares and Additional Shares (prior to July 2019). Restricted Shares will vest two or three years after the date of their award and Additional Shares will vest four or five years after the date of award. Vesting is subject, under normal circumstances, to continued employment during the vesting or ‘restricted’ period. There are no further performance conditions applicable to either Restricted Shares or Additional Shares.
Where awarded, the number of Additional Shares would be equal to 50 per cent of the combined total of shares awarded as Restricted Shares and under the Share Incentive Plan (see section D). No Additional Shares were outstanding at 1 January 2014 and no awards of Additional Shares have been made since this time. intu properties
D Share Incentive Plan (SIP)
The Company operates a SIP for all eligible employees, who may receive up to £3,600 worth of shares (Free Shares) as part of their annual bonus. The SIP is an HMRC tax-advantaged scheme.
Any Free Shares awarded under the SIP will be held in trust on behalf of each employee for at least three years following grant, after which time they may be withdrawn, provided the individual employee has remained in employment with the Company. If the Free Shares are held in trust for a further two years, they will qualify for HMRC-approved tax advantages.
As part of the SIP arrangements, the Company also offers eligible employees the opportunity to participate in a Partnership share scheme, under which employees can invest up to £1,800 of pre-tax salary (or, if less, 10 per cent of salary) in any tax year, which will be used to purchase ordinary shares in the Company (Partnership Shares) at the end of a 12-month period. The Group will give each employee one ordinary share (a Matching Share) for every two Partnership Shares purchased by the employee. Matching Shares will be forfeited if the employee leaves the Group within three years of the date of award and will qualify for HMRC-approved tax advantages if they are held in the SIP for five years.
E Save As You Earn Scheme (SAYE)
The Group operates a SAYE under which all eligible UK employees may save up to a maximum of £500 per month for a period of three or five years and use the proceeds at the end of their saving period to purchase shares in the Company. At the start of the saving period, each SAYE participant will be granted an option to purchase such shares at a price usually determined as the average mid-market closing share price of an ordinary share in the Company over the three consecutive dealing days preceding the SAYE invitation date, discounted by up to 20 per cent. Options may normally be exercised within six months following the end of the savings period.
F Joint Share Ownership Plan (JSOP)
Eligible employees were invited to participate in the JSOP which formed part of the intu properties plc Unapproved Share Option Scheme (which was replaced by the Non-approved Executive Share Option Scheme upon its expiry in April 2018) and the PSP. Under the JSOP, shares are held jointly by the employee and the employee share ownership plan trustee with any increases in the share price and dividends paid on those shares being allocated between the joint owners in accordance with the terms of the scheme.
Conditions under which JSOP interests may be exercised (including applicable performance conditions) are the same as those for the Non-approved Executive Share Option Scheme as outlined in section A.
Table:
 | Note | Outstanding 1 January 2019 | Granted during the year | Exercised during the year | Expired/forfeited during the year | Outstanding 31 December 2019 | Exercisable 31 December 2019
Share Option Schemes | A | 7,938,601 | – | – | (801,528) | 7,137,073 | 5,687,073
Performance Share Plan1 | B | 7,008,260 | 3,734,410 | – | (2,228,278) | 8,514,392 | n/a
Bonus Share Scheme | C | 1,827,366 | 556,840 | (996,503)1 | (16,632) | 1,371,071 | n/a
Share Incentive Plan2 | D | 243,127 | 88,027 | (41,116)1 | (80,736) | 209,302 | n/a
Save As You Earn Scheme | E | 219,136 | 448,368 | – | (121,172) | 546,332 | 60,443
Joint Share Ownership Plan | F | 4,345,305 | – | – | (1,382,972) | 2,962,333 | 2,962,333


Question: What is the percentage change in the outstanding shares under the share options scheme from 1 January 2019 to 31 December 2019?
Answer: -10.1
Calculation: (7,137,073-7,938,601)/7,938,601