##i case illustrates, there is a further argument against over - dependence, namely that it's a two - way street. the dependencies go many ways, and thus the incentives to co - ordinate and co - operate are much larger. in this world, fragmentation would be positively dangerous. underpinning the extensive co - operation and co - ordination are international regulatory standards. they provide a core of assurance to support open financial systems. to be honest, some areas are ahead of others. the basel committee has made most progress, though it is essential that we see a consistent implementation of the so - called basel 3. 1 package. we have more to do in the various parts of the non - bank world, and the financial stability board is very much on the case. but this does not mean that in all jurisdictions the rules must be exactly the same. we are most interested in the outcomes. there will be differences to fit local markets, and again when that is done in a transparent and well understood way, it is sensible and fine. all of that fits within a framework of public policy where the basic objective of financial stability is common, and there should be effective frameworks established through international regulatory standards underpinned by trust and co - operation. to conclude, we must be alert to the pressure for fragmentation, both in the global economy and financial system. the costs that go with such fragmentation are real and undesirable. the better approach is strong articulation of a common public policy objective in terms of financial stability, accompanied by effective co - ordination and cooperation. these are not impossible ideals – we have real evidence of the system working. thank you. i am grateful to sarah breeden, lee foulger, karen jude, rhys phillips, danny walker and michael yoganayagam for helpful comments and assistance in helping me to prepare these remarks. 1 sasha mills speech at the isda derivatives and trading forum, 7 november 2023. 4 / 4 bis - central bankers'speeches

3 % of gdp in 2007. these surpluses were assigned, in part, to the reserve fund, which reached a significant size of close to 5 % of gdp at the end of 2008. in the past year, however, the impact of the economic crisis has also been felt in the social security accounts, meaning there has been a rapid deterioration in this surplus, which could even disappear within a year. analysis of the social security system should not, however, be based on its results in the short term. the signing of the toledo pact was but an acknowledgement that the viability of a pay - as - you - go pension system should be analysed from a long - term perspective. taking this perspective, i should stress that, according to analyses conducted by national and international analysts and institutions, neither the social security surpluses of the past decade nor the foreseeable worsening of the financial situation in the coming years will essentially alter the diagnosis. accordingly, we may assert that the problems relating to the financial sustainability of the current social security system were the same ones that led at the time, among other reasons, to the signing of the pact. there are essentially two factors at the root of these problems : the sharp reduction in the birth rate and the progressive rise in life expectancy, both of which bear on the current and future structure of the spanish population pyramid. on one hand, the outcome of the increase in life expectancy will see the over - 65 segment progressively gain weight in the population total, while the pyramid base will narrow as a result of the birth rate falling below replacement levels. consequently, the shape of the population age structure is changing from its current pyramid form to look more like a pillar. this will be so even assuming some pick - up in the birth rate and continuing positive migrant inflows into spain. in sum, on eurostat's current population projections, prepared in 2008, the dependency ratio ( the over65s as a proportion of the working - age population ) might more than double between 2008 and 2050 from 24 % to almost 59 %. everybody is aware of the consequences of these population developments for the sustainability of our pay - as - you - go pension system. growing pressure would build up on pension spending, meaning that the models currently available, including those devised by the economy and finance and labour and social security ministries which incorporate all the legislative amendments approved in recent years, show that this public spending item would double over the time period referred to